Thanks for taking the time to answer, Ben! :)
From the error description, it appears that this issue is caused due to an input/output device error...
I agree, that's what the error implies, but I think it's misleading, a red herring. I don't think there's anything wrong with any disk. Here's why I think that:
The PC I am running is about 6 years old, it started as a Win 7 system, with an 128GB SSD C: drive.
I then upgraded to Win 8, changing the C: drive to a 256GB SSD at the same time.
Now I am running Win 8.1.
I was always backing up to an external USB3.0 hard drive... and now most recently to a network NAS location.
... and these errors with System Image Backups have occurred intermittantly for all the past 6 years! And I have run CHKDSK /R every time on source and destination as advised, and it has never found a problem on any drive in all those 6 years :)
In the past, simply disabling services/background processes has solved the problem, but with Windows 8.1, it has become more stubborn.
Method 1:
...
b) In the services window, locate the services ‘File history service’ and the ‘Volume shadow copy service’ and check if they are running.
I checked the services: the File History service is set to start-up type 'automatic' and is running.
The Volume Shadow Copy service is set to start up type 'manual' and isn't running until I launch the System Image backup, at which point it starts successfully.
So no problem there.
Method 2:
If the issue persists, I would suggest you to choose a different location to save the backup or try choosing a DVD disc as the backup location and check if that works.
Well I have tried an external USB 3.0 Seagate drive, and a WD NAS on my home LAN. It doesn't work with either of them. I don't think it's a problem with either of these devices. They pass all their own diagnostics and
I've successfully written and read many many terabytes of data to them.
I haven't tried DVD's, but the backup is 81GB so it would take a lot of them and not be very convenient!
Method 3:
If the issue still persists, I would suggest you to boot the computer in a clean boot state and then check
OK, I will give this a go!
I've tried disabling a lot of bits and pieces, not not as thorough or complete as the clean boot.
(I also tried to run in "Safe Mode with Networking", but File History isn't available in that mode).
Will let you know in a couple of hours how I get on.