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