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BackupAssist365 v1.22.1 (59.5 MB)

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Best practice guides

BackupAssist 365

Cheat Sheet for Microsoft 365 (Office 365) backups

  • Getting started and installation
  • Setting up your backup jobs
  • Scheduling, backup windows and your first full backup
  • Backup History, Deleted Items, Old Versions, and Restore
  • Managing your backup destination
  • Data security

Release notes

BackupAssist 365 v1.9.1

New, friendlier Graphical User Interface (GUI)

BackupAssist 365 v1.9.0.5

Provides command line interface for batch mailbox restore.

Display license status in the backup report.

Ignore the “Internal Server Error” in Exchange Server that is caused when trying to back up appointments created by Microsoft Teams when one of the recipients has a bad email address, triggering an “Undeliverable” message.

Fix some HTML scrolling issues at the top of email reports, to make them read better on mobile devices.

BackupAssist 365 v1.9.0.4

Limit the length of the PST password in the GUI.

Fetch all users for OneDrive for Business, not just the first 100.

More resilient parsing of multi-mailbox usernames/passwords when supplied via CSV file or clipboard.

Fixed rare cases where system problems can stop Mailbox backups from running, causing them to hang at “Connecting…”. Instead, BackupAssist 365 will gracefully handle this and attempt the backup at the next scheduled time.

BackupAssist 365 v1.9.0.3

Mailboxes: fixed “Error 1168” if two duplicated items in a folder are moved where one item is deleted and another is moved to a different folder.

SharePoint: fixed crash when listing SharePoint sites if one site contains Extended ASCII characters but not unicode characters in its name.

SharePoint & OneDrive for Business: handle out of disk space and stop the backup preemptively to avoid system problems

Fix problem where email reports were not sent if using ASCII reports via the BackupAssist cloud service.

Fixed GUI crash when viewing skipped items for a deleted backup task.

BackupAssist 365 v1.9.0.2

Mailbox backups: handle situations where there’s throttling or internal Office 365 failures. These used to result in backup failures. Now instead, automatic retries are attempted.

OneDrive for Business: fix false positive warnings that a user’s private files cannot be backed up.

Handle file backups where the file was updated during the backup run.

BackupAssist 365 v1.9.0.1

Fix token expiry problem where some tasks stop running after 90 days.

Fix bug where a Mailbox backup hangs if the entire mailbox is throttled when connecting.

BackupAssist 365 v1.9.0.0

SharePoint backups now free; implemented license usage reports.

Stability enhancements for file downloads.


BackupAssist 365 v1.8.2


Backup Windows: implement a maximum run time to stop a backup if it runs too long.

File downloads: temp files are now used when downloading files to eliminate possibility of corruption in the event of hardware failure or power outage.

File downloads: deal with temporary cloud outages with automatic retries

SharePoint: Automatic permissions granting on demand so you can backup sites that you don’t have permissions to yet.

Mailbox downloads: preserve folder path when moving deleted items to Historical Items

BackupAssist 365 v1.8.1


OneDrive for Business enhancements:

  • Automatic permissions granting to the backup user – all you need is a backup user with SharePoint Admin and Application Admin roles, and OneDrive for Business backups will work seamlessly
  • Better handling of edge cases like network timeouts, intermittent O365 outages and throttling
  • Validation to catch invalid file selections

Diagnostics enhancements:

  • When you submit diagnostics to us, a summary of the backup configuration is now generated to make debugging easier.

Bug fixes:

  • Fixed bug where undo delete worked but the GUI was not updated
  • Fixed bug where multi-user O365 / Exchange backup tasks were detected as single-user tasks in the Edit Task GUI.

BackupAssist 365 v1.8.0


Numerous enhancements in the Progress & Log user interface:

  • Filter the view of active backups by backup task and date
  • View past backup reports
  • See which items are skipped during a backup – such as emails with attachments that failed a virus scan

Reporting enhancements:

  • Only include warnings and errors in the top section of backup reports.

Mailbox backup enhancements:

  • Fast reconnections after network problems
  • Write protect PST files, and include a readme.txt to discourage users from opening the backup files directly.

Bug fixes:

  • Fixed bug where Public Folder backup was not working.
  • Fixed bug where multi-user IMAP backup tasks were detected as single-user tasks in the Edit Task GUI.


BackupAssist 365 v1.7.1


User experience enhancements:

  • Always use private browsing mode by default when logging in to Office 365
  • Expanded list of supported browsers for authenticating – IE, Edge, Firefox, Opera, Chrome, AVG, Brave
  • Improved calendar control allows faster input of months and years

Network Share support as a destination

Mailbox backup enhancements:

  • Support for TLS 1.2 connections – required when TLS 1.0 and 1.1 are disabled on an Exchange Server
  • Compatibility with Exchange Server 2019

BackupAssist 365 v1.7.0

Support modern authentication for Mailbox downloads:

  • Allow user to log in via web browser.
  • Allow user to connect when MFA is turned on.

SharePoint enhancements:

  • Support backing up multiple Document Libraries per SharePoint Site, from a single backup task and login

Store application save data to the ProgramData directory instead of the system user profile directory.

Bug fixes:

  • Fixed bug where occasionally, active backup logs would disappear if the GUI is running for over 7 days.

BackupAssist 365 v1.6.2

Mailbox backup enhancements:

  • Handle throttling situations with users who have thousands of Calendar items. Around 500-1000 calendar items can be downloaded per day, before O365 starts to throttle. Upon throttling, BA365 will skip the folder and continue with the remainder of the mailbox. In practice, this means the calendar will now be downloaded over several days, while remaining data is backed up correctly.

Support for community builds:

  • The same licence key will now work with community builds and official release builds.

Bug fixes:

  • Fixed bug where “Suggested Contacts” folder on German systems with data from Outlook 2010 was crashing the backup.
  • Fixed bug where SharePoint and OneDrive for Business backups will correctly terminate if the network connection has been down for over 10 minutes, and all attempts to reconnect have failed.

BackupAssist 365 v1.6.1

Mailbox backup enhancements:

  • Connect to Office 365 using the Exchange 2016 interface, instead of Exchange 2013. This solves issues where error messages from Office 365 like “The property Hashtags is valid only for Exchange Exchange2015 or later versions.” are shown.

Improved reporting:

  • Introduced a new Info level for report messages, so small issues can be logged without generating warnings or errors. This is mainly to deal with edge cases that are inconsequential, and should not demand attention from the administrator, because they make no tangible difference to the integrity of the backups. Examples of this are:
    1. An email attachment contains a virus, so the email is skipped over in the backup.
    2. There was a transient error in Office 365 (service temporarily unavailable) so a folder or file was skipped, but it will be backed up next time the backup runs. This handles error messages such as “Specified object not found in store”.
    3. Office 365 is internally moving data around in its datacenters, resulting in messages such as “Exchange Web Services are not currently avaialble for this request because none of the Client Access Servers in the destination site could process the request” or “Mailbox move in progress”

Allow the Service to run as different user identity without losing configuration settings:

  • The configuration encryption key is now derived from the system identity, not the user identity.

Bug fixes:

  • Fixed bug in Mailbox backups where reserved characters such as “, <, >, in a folder name will cause a backup failure.

BackupAssist 365 v1.6.0

Mailbox backup enhancements:

  • PST files are now extremely compact, with upwards of 99% space utilisation.
  • Handle throttling better: if one mailbox is throttled, BA365 will detect this and skip over to the next mailbox, so that one throttled mailbox will not halt the entire backup.
  • Implemented a maximum number of retries per throttled mailbox.

OneDrive for Business enhancements:

  • Support for backing up multiple user accounts from a single backup task and login.

Improved reporting:

  • Skipped item messages are now logged against the mailbox or user storage account, instead of globally.
  • Handle Office 365 transient errors better: “Mailbox Move in Progress”, “The specified object not found in store” now only generates a warning, not a failure.

Bug fixes:

  • Fixed bug for SharePoint and OneDrive for Business backups where files that contain a ‘#’ character would be skipped and raise an error.