How to Fix Backup Error 0x807800C5 in Windows 10

Before we fix backup error 0x807800C5, here is the error that you get,

There was a failure in preparing the backup image of one of the volumes in the backup set. Details: The I/O operation has been aborted because of either a thread exit or an application request.

This error comes up while you try to back up system images of your Windows 10 PC to Network-Attached Storage.

How to Fix Backup Error 0x807800C5 on Windows 10

Now to fix the error, follow the steps given below.

1. Get access to the NAS or the NAS shell.  This is important as you will need to get to the location of the original system image stored there.
2. Now look for the original system image.
3. Once you locate it, rename it like: __nas_backup_WindowsImageBackup_host-name to __nas_backup_WindowsImageBackup_host-name.bak.
4. Then go back to your Windows 10 PC.
5. Now you should run Windows 10 Image Backup. Try to backup a system image of your PC to NAS.
6. This time it should work fine with no error.

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