{"id":14394,"date":"2019-11-15T04:42:03","date_gmt":"2019-11-15T04:42:03","guid":{"rendered":"https:\/\/www.backupassist.com\/blog\/?p=14394"},"modified":"2021-05-30T23:44:27","modified_gmt":"2021-05-30T23:44:27","slug":"office-365-exchange-mailbox-backup-stall","status":"publish","type":"post","link":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall","title":{"rendered":"Mailbox backup from Office 365 or Exchange &#8211; why does BackupAssist 365 sometimes appear to go slowly or stall?"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">TL;DR summary<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>When performing a mailbox backup from Office 365, progress may slow down unexpectedly, especially when processing<span style=\"font-size: inherit; background-color: initial; font-family: -apple-system, system-ui, BlinkMacSystemFont, &quot;Segoe UI&quot;, Helvetica, Arial, sans-serif, &quot;Apple Color Emoji&quot;, &quot;Segoe UI Emoji&quot;, &quot;Segoe UI Symbol&quot;;\"> the &#8220;Calendar&#8221; folder<\/span><\/li><li>There are two main causes of a slowdown:<ul><li>Throttling at the Exchange Server end.<\/li><li>Dirty data that causes server-side errors within Exchange Server. This requires special handling at the BackupAssist 365 end.<\/li><\/ul><\/li><li>BackupAssist 365 is engineered for performance and resilience, and deals with this with high efficiency \u2013 despite the appearance of a stall.<\/li><li>It\u2019s generally nothing to worry about. Backups will complete over a number of runs.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Backing up Office 365 mailboxes to local PST files \u2013 how we engineered for performance with large batches<\/h2>\n\n\n\n<p>On the whole, BackupAssist 365 has been optimized for\nperformance when downloading mailboxes from Office 365 or Exchange to PST file.<\/p>\n\n\n\n<p>A key part of this is minimizing the number of requests to the server. Each request incurs latency, and therefore is expensive. By default, BackupAssist 365 will download mailbox items from Office 365 or Exchange in large batches, such as 400 items at a time. <\/p>\n\n\n\n<p>There are occasional circumstances where it might appear\nthat BackupAssist 365 gets \u201cstuck\u201d or slows down \u2013 especially with Calendar\nitems. In the progress log, you might see a message like:<\/p>\n\n\n\n<p>\u201cDownloading items 1 to 400 from Calendar\u201d \u2013 and this message may stay there for minutes.<\/p>\n\n\n\n<p>In the backup progress log and report, you may also see messages like: <\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>The mailbox is throttled on folder &#8216;Calendar&#8217;. Skipping this folder &#8211; the backup will continue on the next run.<\/p><\/blockquote>\n\n\n\n<p>Note: this problem can occur whether you use a <a href=\"https:\/\/www.backupassist.com\/blog\/back-up-multiple-office-365-mailboxes-with-a-single-backup-user-login\">single login to back up multiple mailboxes<\/a>, or not.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Cause 1: Throttling at Microsoft Exchange Server<\/h2>\n\n\n\n<p>Throttling is something that users may encounter when the Exchange Server cannot handle the load of requests from all the users it serves. This means that it&#8217;s not predictable, and does not happen for every person.<\/p>\n\n\n\n<p>Most human users will never notice this, because if Outlook fails to sync due to throttling, it&#8217;s generally invisible to the user. However, backup software for Office 365 like BackupAssist 365 will report this occurrence, because if throttling happens, backups will take multiple runs to complete.<\/p>\n\n\n\n<p>We&#8217;ve found that Calendar items are particularly problematic. A summary of our findings are:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>BackupAssist 365 can generally download 400 to 1000 calendar items per user per run before throttling happens.<\/li><li>Downloading Calendar items is slower than regular emails.<\/li><li>If BackupAssist 365 detects that Exchange is throttling and not delivering any additional calendar items, it will skip the folder and continue the rest of the backup.<\/li><li>Mailboxes with many calendar items will take several runs to complete. For example, a mailbox with 10,000 items can be expected to take between 10 and 25 runs to complete.<\/li><\/ul>\n\n\n\n<p>In our experiments, we&#8217;ve found that other applications like Outlook also encounter throttling, especially on calendar items. Outlook also downloads these items gradually.<\/p>\n\n\n\n<p><strong>The take-home message from this is &#8211; don&#8217;t worry. BackupAssist 365 will download as much data as it can on each backup run. Some mailboxes will just take multiple backup runs to complete<\/strong>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Cause 2: Dirty data in the mailbox is not possible to back up<\/h2>\n\n\n\n<p>If throttling is not the cause, then almost always, the cause of the slowdown is dirty data. Here\u2019s why.<\/p>\n\n\n\n<p>When we issue the commands to backup a mailbox from Office 365 or Exchange, along the lines of \u201cfetch items #1 to #400 from the Calendar folder\u201d, the server will retrieve those items and return them in one operation. <\/p>\n\n\n\n<p>However, occasionally we get an error message instead. If <strong>just one<\/strong> of those items is \u201cdirty\u201d \u2013 that means, if it does not confirm to the expected data format \u2013 then the Exchange server will throw an error, instead of returning any data.<\/p>\n\n\n\n<p>(We\u2019ll explain how dirty data gets into a mailbox a bit\nlater.)<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Why it can get slow (the price of resilient backups for Office 365 and Exchange)<\/h3>\n\n\n\n<p>In the example above, instead of skipping ignoring the error returned from the server and skipping all 400 items, the correct thing to do is to download every item that isn\u2019t \u201cdirty\u201d.<\/p>\n\n\n\n<p>But how do we know which one of the 400 items is the dirty one? Unfortunately, we don\u2019t. We have to search for it&#8230; and the most efficient way to search for the dirty data is to do a kind of binary search: to break the request for 400 items into two requests for 200 items. Somewhere, one of those requests will fail. Then we break the next failed requests into two requests for 100 items. And then down to two requests for 50 items. And so on\u2026 until we have downloaded everything we can.<\/p>\n\n\n\n<p>This means that the number of requests to the server will explode. <\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Here&#8217;s an example<\/h3>\n\n\n\n<p>In the example above, let\u2019s say that item #2 is dirty but every other item is normal, then you\u2019d see behaviour something like this:<\/p>\n\n\n\n<p><code><\/code><\/p>\n\n\n\n<code>1.\tFetch 400 items (#1 - #400) \u2013 failed<br>\n2.\tFetch 200 items (#1 - #200) \u2013 failed<br>\n3.\tFetch 200 items (#201 - #400) \u2013 success<br>\n4.\tFetch 100 items (#1 - #100) \u2013 failed<br>\n5.\tFetch 100 items (#101 - #200) \u2013 success<br>\n6.\tFetch 50 items (#1 - #50) \u2013 failed<br>\n7.\tFetch 50 items (#51 - #100) \u2013 success<br>\n8.\tFetch 25 items (#1 - #25) \u2013 failed<br>\n9.\tFetch 25 items (#26 - #50) \u2013 success<br>\n10.\tFetch 13 items (#1 - #13) \u2013 failed<br>\n11.\tFetch 12 items (#14 - #25) \u2013 success<br>\n12.\tFetch 7 items (#1 - #7) \u2013 failed<br>\n13.\tFetch 6 items (#8 - #13) \u2013 success<br>\n14.\tFetch 4 items (#1 - #4) \u2013 failed<br>\n15.\tFetch 3 items (#5 - #7) \u2013 success<br>\n16.\tFetch item #1 \u2013 success<br>\n17.\tFetch item #2 \u2013 failed<br>\n18.\tFetch item #3 \u2013 success<br>\n19.\tFetch item #4 \u2013 success<br>\n<\/code>\n\n\n\n<p><\/p>\n\n\n\n<p>So in the example above, there are 19 times the number of\nrequests to Exchange caused by one dirty item.<\/p>\n\n\n\n<p>In summary you can see,<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>It takes 1 request to get 400 items when all\nitems are clean, and<\/li><li>It takes 19 requests to get 399 items when one\nitem is dirty.<\/li><\/ul>\n\n\n\n<p>The more dirty items there are, the more number of server\nrequests are needed. Because we don\u2019t know how many dirty items there are in a\nbatch, doing the binary search is going to be the most efficient way to ensure\nwe back up all the valid items.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What causes the dirty data in Office 365 or Exchange mailboxes?<\/h3>\n\n\n\n<p>We are not exactly sure what the causes are. We have noticed\nthat it is more prevalent with data that has been migrated one or more times.\nFor example, it happened on our own on-premise Exchange Server when data had\nbeen migrated from Exchange 2003 to Exchange 2007 to Exchange 2010, and also\nincluded data added from PST files using Outlook. <\/p>\n\n\n\n<p>Any fault with the EDB files in Exchange, or faulty copying\nform PST files, or any bug in Outlook clients could have caused the problem.\nAnother possibility is 3<sup>rd<\/sup> party applications and mail clients that\nadd items to a mailbox. If these clients introduced data that did not meet the\nrequired specifications, that 3<sup>rd<\/sup> party app might appear to work but\ncause problems with backups.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p>When designing BackupAssist 365, we had to engineer it for\nreliability and dependability. As explained above, that means sometimes performance\nappears to slow down when there is dirty data present. The server returns an\nerror when trying to retrieve the dirty data.<\/p>\n\n\n\n<p>Despite the appearance of a stall, BackupAssist 365 attempts to handle the presence of dirty data in the most efficient way possible. Therefore, the Office 365 mailbox backup PST files will contain all the valid items in it. <\/p>\n\n\n\n<p>If you experience a slowdown or stall lasting more than an hour, please contact our technical support department and we\u2019ll investigate it further.<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>Image credit: Photo by\u00a0<a href=\"https:\/\/unsplash.com\/@epicantus?utm_source=unsplash&amp;utm_medium=referral&amp;utm_content=creditCopyText\">Daria Nepriakhina<\/a>\u00a0on\u00a0<a href=\"https:\/\/unsplash.com\/?utm_source=unsplash&amp;utm_medium=referral&amp;utm_content=creditCopyText\">Unsplash<\/a><\/p>\n\n\n\n<p>Article last updated: 31 May 2021<\/p>\n","protected":false},"excerpt":{"rendered":"<p>When doing a backup of mailboxes in Office 365 or Exchange to a local PST file, there are situations where BackupAssist 365 appears to slow down or stall. Here&#8217;s why.<\/p>\n","protected":false},"author":2,"featured_media":14458,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-14394","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v24.9 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog<\/title>\n<meta name=\"description\" content=\"BackupAssist 365 may appear &quot;stalled&quot; when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here&#039;s why.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog\" \/>\n<meta property=\"og:description\" content=\"BackupAssist 365 may appear &quot;stalled&quot; when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here&#039;s why.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\" \/>\n<meta property=\"og:site_name\" content=\"Cyber Resilience Blog\" \/>\n<meta property=\"article:published_time\" content=\"2019-11-15T04:42:03+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2021-05-30T23:44:27+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"3200\" \/>\n\t<meta property=\"og:image:height\" content=\"1803\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Linus Chang\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Linus Chang\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"6 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\"},\"author\":{\"name\":\"Linus Chang\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/523a9a01769da254de228dbd4b1328d3\"},\"headline\":\"Mailbox backup from Office 365 or Exchange &#8211; why does BackupAssist 365 sometimes appear to go slowly or stall?\",\"datePublished\":\"2019-11-15T04:42:03+00:00\",\"dateModified\":\"2021-05-30T23:44:27+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\"},\"wordCount\":1145,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/#organization\"},\"image\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg\",\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\",\"url\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\",\"name\":\"Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog\",\"isPartOf\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage\"},\"thumbnailUrl\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg\",\"datePublished\":\"2019-11-15T04:42:03+00:00\",\"dateModified\":\"2021-05-30T23:44:27+00:00\",\"description\":\"BackupAssist 365 may appear \\\"stalled\\\" when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here's why.\",\"breadcrumb\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage\",\"url\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg\",\"contentUrl\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg\",\"width\":3200,\"height\":1803},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.backupassist.com\/blog\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Mailbox backup from Office 365 or Exchange &#8211; why does BackupAssist 365 sometimes appear to go slowly or stall?\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#website\",\"url\":\"https:\/\/www.backupassist.com\/blog\/\",\"name\":\"Cyber Resilience Blog\",\"description\":\"Protect Your Cloud Data with BackupAssist\",\"publisher\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.backupassist.com\/blog\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#organization\",\"name\":\"Cyber Resilience Blog\",\"url\":\"https:\/\/www.backupassist.com\/blog\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/09\/BA-Logo-Full-Logo.svg\",\"contentUrl\":\"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/09\/BA-Logo-Full-Logo.svg\",\"caption\":\"Cyber Resilience Blog\"},\"image\":{\"@id\":\"https:\/\/www.backupassist.com\/blog\/#\/schema\/logo\/image\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/523a9a01769da254de228dbd4b1328d3\",\"name\":\"Linus Chang\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/58a69ed0d0b9928d91dec6132dccfb646cc4230839af779f185531c722b0d017?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/58a69ed0d0b9928d91dec6132dccfb646cc4230839af779f185531c722b0d017?s=96&d=mm&r=g\",\"caption\":\"Linus Chang\"},\"description\":\"*Founder &amp; Creator, BackupAssist* Linus Chang has been writing software since he was eight years old. He founded BackupAssist in 2002 \u2014 making him one of the longest-standing voices in Windows backup and data protection \u2014 and has spent the decades since talking to IT administrators around the world about what actually goes wrong, and why. His interest in data loss isn't abstract. Early in his career, he was working at the Monash University help desk when a student came in with a floppy disk that wouldn't read. They tried everything. None of their drives could read it either. The disk held her entire PhD dissertation \u2014 years of work \u2014 and it was the only copy. She broke down in tears. There was nothing he could do. Five years later, he wrote the first version of BackupAssist. Linus holds a Bachelor of Science in Computer Science and has held Microsoft Certified Solution Developer and Sun Certified Java Programmer credentials. More recently, he has completed digital forensics and cyber-security courses through the Black Hat Conference. He has spoken on information security and cryptography at Infosecurity Europe, addressed politicians and policymakers at Australian Parliament House, presented to SMB IT administrators at the IT Pro Experts Conference, and served as a guest lecturer to Cyber Security master's students at the University of Melbourne. On this blog, Linus writes about backup strategy and the technical side of cyber-resilience \u2014 drawing on 24 years of product development and direct conversation with the IT professionals BackupAssist is built for. [Connect with Linus on LinkedIn](https:\/\/www.linkedin.com\/in\/linuschang\/)\",\"url\":\"https:\/\/www.backupassist.com\/blog\/author\/linus-chang\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog","description":"BackupAssist 365 may appear \"stalled\" when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here's why.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall","og_locale":"en_US","og_type":"article","og_title":"Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog","og_description":"BackupAssist 365 may appear \"stalled\" when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here's why.","og_url":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall","og_site_name":"Cyber Resilience Blog","article_published_time":"2019-11-15T04:42:03+00:00","article_modified_time":"2021-05-30T23:44:27+00:00","og_image":[{"width":3200,"height":1803,"url":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg","type":"image\/jpeg"}],"author":"Linus Chang","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Linus Chang","Est. reading time":"6 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#article","isPartOf":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall"},"author":{"name":"Linus Chang","@id":"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/523a9a01769da254de228dbd4b1328d3"},"headline":"Mailbox backup from Office 365 or Exchange &#8211; why does BackupAssist 365 sometimes appear to go slowly or stall?","datePublished":"2019-11-15T04:42:03+00:00","dateModified":"2021-05-30T23:44:27+00:00","mainEntityOfPage":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall"},"wordCount":1145,"commentCount":0,"publisher":{"@id":"https:\/\/www.backupassist.com\/blog\/#organization"},"image":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage"},"thumbnailUrl":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg","inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall","url":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall","name":"Office 365 mailbox backup - why does it stall? - Cyber Resilience Blog","isPartOf":{"@id":"https:\/\/www.backupassist.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage"},"image":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage"},"thumbnailUrl":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg","datePublished":"2019-11-15T04:42:03+00:00","dateModified":"2021-05-30T23:44:27+00:00","description":"BackupAssist 365 may appear \"stalled\" when doing a mailbox backup from Office 365 and Exchange Mailboxes to PST file. Here's why.","breadcrumb":{"@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#primaryimage","url":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg","contentUrl":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/11\/coffee-break.jpg","width":3200,"height":1803},{"@type":"BreadcrumbList","@id":"https:\/\/www.backupassist.com\/blog\/office-365-exchange-mailbox-backup-stall#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.backupassist.com\/blog"},{"@type":"ListItem","position":2,"name":"Mailbox backup from Office 365 or Exchange &#8211; why does BackupAssist 365 sometimes appear to go slowly or stall?"}]},{"@type":"WebSite","@id":"https:\/\/www.backupassist.com\/blog\/#website","url":"https:\/\/www.backupassist.com\/blog\/","name":"Cyber Resilience Blog","description":"Protect Your Cloud Data with BackupAssist","publisher":{"@id":"https:\/\/www.backupassist.com\/blog\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.backupassist.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.backupassist.com\/blog\/#organization","name":"Cyber Resilience Blog","url":"https:\/\/www.backupassist.com\/blog\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.backupassist.com\/blog\/#\/schema\/logo\/image\/","url":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/09\/BA-Logo-Full-Logo.svg","contentUrl":"https:\/\/www.backupassist.com\/app\/uploads\/sites\/3\/2019\/09\/BA-Logo-Full-Logo.svg","caption":"Cyber Resilience Blog"},"image":{"@id":"https:\/\/www.backupassist.com\/blog\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/523a9a01769da254de228dbd4b1328d3","name":"Linus Chang","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.backupassist.com\/blog\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/58a69ed0d0b9928d91dec6132dccfb646cc4230839af779f185531c722b0d017?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/58a69ed0d0b9928d91dec6132dccfb646cc4230839af779f185531c722b0d017?s=96&d=mm&r=g","caption":"Linus Chang"},"description":"*Founder &amp; Creator, BackupAssist* Linus Chang has been writing software since he was eight years old. He founded BackupAssist in 2002 \u2014 making him one of the longest-standing voices in Windows backup and data protection \u2014 and has spent the decades since talking to IT administrators around the world about what actually goes wrong, and why. His interest in data loss isn't abstract. Early in his career, he was working at the Monash University help desk when a student came in with a floppy disk that wouldn't read. They tried everything. None of their drives could read it either. The disk held her entire PhD dissertation \u2014 years of work \u2014 and it was the only copy. She broke down in tears. There was nothing he could do. Five years later, he wrote the first version of BackupAssist. Linus holds a Bachelor of Science in Computer Science and has held Microsoft Certified Solution Developer and Sun Certified Java Programmer credentials. More recently, he has completed digital forensics and cyber-security courses through the Black Hat Conference. He has spoken on information security and cryptography at Infosecurity Europe, addressed politicians and policymakers at Australian Parliament House, presented to SMB IT administrators at the IT Pro Experts Conference, and served as a guest lecturer to Cyber Security master's students at the University of Melbourne. On this blog, Linus writes about backup strategy and the technical side of cyber-resilience \u2014 drawing on 24 years of product development and direct conversation with the IT professionals BackupAssist is built for. [Connect with Linus on LinkedIn](https:\/\/www.linkedin.com\/in\/linuschang\/)","url":"https:\/\/www.backupassist.com\/blog\/author\/linus-chang"}]}},"_links":{"self":[{"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/posts\/14394","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/comments?post=14394"}],"version-history":[{"count":12,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/posts\/14394\/revisions"}],"predecessor-version":[{"id":17509,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/posts\/14394\/revisions\/17509"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/media\/14458"}],"wp:attachment":[{"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/media?parent=14394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/categories?post=14394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.backupassist.com\/blog\/wp-json\/wp\/v2\/tags?post=14394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}