Disk Error Messages with ASPI2DOS.SYS Device Driver (94331)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.0
    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 Q94331


ASPI2DOS.SYS is an Adaptec driver for the Adaptec AHA 1520 and AHA 1522 SCSI controllers. If SMARTDrive is used to cache a drive when ASPI2DOS.SYS is installed, you may receive the following error message from the Adaptec controller:

A serious disk error has occurred while writing to drive C.
When you run Microsoft Anti-Virus (MSAV.EXE), you receive the following error message:

Not ready reading (or writing) drive C:
Similar errors may also occur while running Microsoft Defragmenter (DEFRAG.EXE) and Microsoft Undelete (UNDELETE.EXE).

NOTE: The SMARTDrive double-buffer driver does not prevent these errors.


This problem occurs if you use the ASPI2DOS drivers shipped with EZSCSI versions 2.02 and 2.03.


This problem was corrected in EZSCSI versions 2.04, 3.0, and later. These are available for free from Adaptec.


This problem usually occurs during frequent alternating reads and writes by programs such as Microsoft Anti-Virus and SMARTDrive.

Modification Type: Major Last Reviewed: 11/16/1999
Keywords: KB94331