My personal computer has an Intel SSD for the boot drive (C:) and a RAID5 array for data storage (D:). Because D: is a RAID5 array, it is fault tolerant. If one of the three drives fails, I can replace it without losing any data. C: is just a single drive, so if it failed the data would be lost. To prevent this, I had configured the Windows 7 backup utility to save a system image of the C: drive to D: each night.
This worked fine for a while until I started getting notification that my backup had failed. Checking the Application log I saw that Windows Backup was throwing the following error each time it tried to run.
The backup was not successful. The error is: The backup storage location is invalid. You cannot use a volume that is included in the backup as a storage location. (0x80780040).
I went back into the Windows Backup configuration and found that I was no longer able to select the D: drive as the save location for the system image! After doing some research, I found that when saving a system image, Windows Backup will include all drives that have system files including any programs which are installed as a service.
I then remembered that I had recently installed the Folding@Home SMP client as a service with the files stored on the D: drive of my PC. This was the problem. I uninstalled the F@H service and then moved the files to the C: drive and reinstalled the MPICH client (install.bat) and the F@H service.
Once that was done, I was able to choose the D: drive as the system image storage location again, and my backups have been going through each night without error.
If you are getting this error and don’t remember installing a service to the storage location, you can manually check where each service is starting from. Start regedit and browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services. Check the ImagePath value of each subkey; this is the location of the file that is run for each service. If any of the ImagePath keys point to your storage location, the backup will not go through until they are removed or reconfigured.