This article explains common reasons for backup and recovery failures and warnings and provides guidance on how to troubleshoot and resolve these issues.
How to view and check tasks finished with Failed or Warning status
If any of backup or recovery tasks has finished with Failed or Warning status you will see non-zero number of Fails or Warnings in the Backup statuses chart in the Overview dashboard. You can configure service reports at the Configuration → Reports tab to receive periodic emails or Slack/Teams notifications with licensing and protection/backup status for a tenant.
To find affected resources and files, please go to the Activity → Tasks tab and filter out tasks with Failed or Warning status, after that you can view each task details by clicking on them and review a failure reason or affected files.
Backup and recovery failures
Most common backup failures:
- Quota exceeded - an Afi tenant exceeds its licensed user or storage quota. Please go to the Licensing → Subscriptions tab to review the available quota and current service usage or adjust the license counts.
Most common recovery failures:
- Drive API is disabled for the account - an attempt to restore OneDrive data to a user without an active SharePoint license or without a provisioned OneDrive service. In such cases we recommend to check Microsoft 365 licenses assigned to the affected user or log in to the user and open its OneDrive web interface to force it to be provisioned.
Backup and recovery warnings
In rare cases a backup task can finish with a warning when it fails to download one or more items (files, emails, etc) from Microsoft 365. The common reasons why it happens are the following:
- Can't download the item due to exceeded provider quota on this resource, will retry later - generally, this warning is encountered during Contacts or Calendars backup when Exchange mailbox limits for an affected mailbox are exceeded (https://docs.microsoft.com/en-us/office365/servicedescriptions/exchange-online-service-description/exchange-online-limits). In particular, if there are too many contacts in the Deleted items folder for the Contacts part of the Exchange mailbox or if the mailbox size on Microsoft 365 side exceeds its limits imposed by Microsoft. Afi recommends to check the problematic mailbox limits or cleanup some deleted items to unblock the backup.
- Can't download the item due to API errors, probably it is corrupted, will retry later - the affected file can't be retrieved through Microsoft 365 API and is likely corrupted. In this case we suggest to try opening the file via OneDrive/SharePoint web interface to check if it is accessible. If the file is accessible, you can download it from OneDrive/SharePoint, then delete the corresponding file on Microsoft 365 side and after that upload it to OneDrive/SharePoint again. Alternatively, if the file can't be downloaded from Microsoft 365, you can replace the corrupted file in OneDrive/SharePoint with a correct copy from one of the previous backups.
- OneDrive API is not available - OneDrive data for an affected user is unavailable, typically, when OneDrive service for the user isn't provisioned.
- Can't download the file marked as a malware by Microsoft 365 - the affected file is classified by Microsoft as a malware and is prohibited from being download via Microsoft 365 API.
Paused backups or restores
A typical reason for a paused backup is Microsoft 365 API throttling during an initial data synchronization for a resource (mailbox/drive/site/team/etc). When the Afi service detects an elevated rate of transient errors from Microsoft 365, it pauses an affected task and automatically restarts in a few hours. After a restart such task proceeds from a saved state and continues synchronization. Paused backups usually don't require any manual troubleshooting with API throttling issues being resolved themselves in a few hours and, after an initial data synchronization for a Microsoft 365 tenant is performed, next incremental backups are expected to be fast and run without any disruptions regardless of a resource size.
Also, in rare cases, a backup or a recovery task might get paused due to an accidental non-throttling related error from Microsoft 365. In such cases the task will be paused in an similar manner and usually will be able to finish successfully after the automatic restart by the service. Afi team constantly monitors paused tasks across the service and proactively investigates and troubleshoots any repeating issues.