Thank you for reaching out to us.
First thing, check if there is any anti-virus software is running/scanning the machine while backup is in progress.
If yes, ensure Azure backup agent is added in the AV exclusion list and also make sure the files/volumes being backed up are not blocked by AV
Follow these workaround steps:
• Open the Azure Backup Agent and click on schedule backup.
• Navigate to the option “Select items to backup”
• Remove from the configuration the volume which was selected before, and if you have another volume please select it, for example, D. Since we are doing a test, it might take several minutes, so to avoid that just create a .txt file in D volume and select only that file for the backup.
• Then click on next and finish the configuration.
• Trigger a backup of this new backup item that we selected.
• Once it completes successfully, please re-configure the original settings for the original volume.
This should generate new VHDs ids and files, because when we swap from one volume to another and then we back up to the original volume the agent must do a full backup even when the volume was previously backed up.
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