Why is Acronis not able to backup while Yahoo!, Firefox, or Microsoft Word are running?

Question

I have a scheduled backup with Acronis True Image. But it gives me an error that system is not able to start a backup while Yahoo! Messenger, Firefox, or Microsoft Word is running.

I remember that I have done backups with all these applications running.

Why am I getting this error now?

This is the error

Details: Cannot proceed with operation while application is running.
C:\Program Files (x86)\Microsoft Office\Office12\EXCEL.exe
Close the application and click Retry. To stop the operation click Cancel.: None

More information can be found at: http://kb.acronis.com/errorcode/
Event code: 0x00550018

Answer 1

I also use Acronis True Image, although I usually close all applications when it's running, just in case. It's highly not recommended to modify the hard disk while taking a disk image.

That said, as Acronis uses shadow copy, it shouldn't normally be blocked by any single program. Even system files locked by Windows itself can be copied.

The only suggestion I can come up with is to deeply scan your computer for viruses, which might explain this abnormal behavior. I recommend using at least Malwarebytes' Anti-Malware. I also like Avast.