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Q113163: CPAV Reports COMMAND.COM Infected with Unknown Virus

Article: Q113163
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:6.2
Operating System(s): 
Keyword(s): 
Last Modified: 21-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system version 6.2 
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SYMPTOMS
========

When you run Central Point Anti-Virus (CPAV) version 2.1 prior to running MS-DOS
6.2 Step-Up and then run it again after running Step-Up, CPAV reports the
following message:

  File COMMAND.COM is infected by an unknown virus
  The virus size is 1,694 bytes
  Infection type is End COM
  Clean, Continue or Stop

NOTE: CPAV may also report the above error message for the file TREE.COM. Central
Point Anti-Virus version 9.0 has also exhibited this behavior.

CAUSE
=====

According to Central Point Technical Support, this error is not actually caused
by a virus. Central Point Anti-Virus detects a change in the file size of
COMMAND.COM and reports "unknown virus" based on this change.

The "virus" size is 1,694 bytes, which is exactly the difference in the size of
MS-DOS 6.0 COMMAND.COM and MS-DOS 6.2 COMMAND.COM.

WORKAROUND
==========

According to Central Point Technical Support, you can work around this problem
by choosing Stop when the above message appears. Next, delete the SMARTCHK.CPS
files from the root directory and the DOS directory; or, delete all SMARTCHK.CPS
files on the drive (to do that, choose Delete Smartchecks from the Scan menu in
CPAV. Then, run CPAV again.

MORE INFORMATION
================

For more information, contact Central Point Technical Support.

Central Point Anti-Virus is manufactured by Central Point Software, a vendor
independent of Microsoft; we make no warranty, implied or otherwise, regarding
this product's performance or reliability.

Additional query words: 6.20 9.00

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS620
Version           : MS-DOS:6.2

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