Running SCANDISK /ALL While a Virtual Drive Exists (108496)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q108496


Running SCANDISK /ALL incorrectly scans virtual drives created using the SUBST command.


Microsoft has confirmed this to be a problem in the ScanDisk program included with MS-DOS versions 6.2, 6.21, and 6.22. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.


If you use drive A as a virtual drive (for example, by using the command SUBST A: C:\DOS), running SCANDISK A: results in the following error message

Drive A was created by using the SUBST or ASSIGN command and cannot be checked. To check drive A, run ScanDisk on drive C instead.
The error message recommends running ScanDisk on drive C because the physical directory actually resides on C. This is normal.

If you run SCANDISK /ALL, ScanDisk actually diagnoses the virtual drive. While this should not cause errors, Microsoft recommends that you not run SCANDISK /ALL while a virtual drive exists.

Modification Type: Major Last Reviewed: 11/25/1999
Keywords: KB108496