While working on a Windows XP system today I had to check the system for corrupted system files. Typically we’d just run sfc from the command line, however, this system’s dllcache was corrupted or missing. On a normal system, this wouldn’t be a problem, you’d insert the Windows XP install media this device, however, didn’t have an optical drive, nor would WFP accept the ISO we’d mounted with WinCDEmu. It turns out there is a registry key that indicates the location of the cache, which in our case was set to the location of the optical drive that was no longer present, the drive letter of which was currently mounted to a data drive.
Changing these to reflect the location of our mounted ISO and restarting the scan resolved the issue and we were able to find and repair the corrupted files.
Yes, we’d like to replace this system altogether, none of us like having to run an out of support 16-year-old operating system. However, as it often goes, this system is still critical and we can’t quite get rid of it yet.