We have a Systemax desktop machine running Windows XP Professional SP2. All Microsoft Updates are current (except we're still running SP2 instead of SP3, and have not yet upgraded to IE 7), and we have done full scans with Symantec Anti-Virus, PC Tools Spyware Doctor, and Malwarebytes. No infections or other problems are reported by those tools. The problem is that, when shutting down Windows, we see a message: "The wrong volume is in the drive. Please insert volume in drive C:." [Drive C: is the physical drive on which the operating system is installed. Note that the message does not specify "which" volume to insert.] Clicking Retry does nothing, and clicking Cancel allows the machine to shut down. On each subsequent restart, Windows insists on running chkdsk. We've run chkdsk /r /f from safe mode, with no egregious errors reported. We also have uninstalled the only program installed within the last couple of months, and subsequently run a Registry Cleaner (jv16 Power Tools). The problem persists. I suspect that this is a self-perpetuating problem that originates with the "The wrong volume is in the drive" error, but I can't figure out how to cure that. Any suggestions will be appreciated!