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Author Topic: Windows Error for "16 bit MS-DOS Subsystem"  (Read 1392 times)

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Windows Error for "16 bit MS-DOS Subsystem"
« on: April 11, 2009, 11:05:01 AM »
Hello all,
I am running Windows XP Home Edition SP3 with a Celeron 2.2GHz CPU and 1.00GB of RAM.  I am directly connected to my service providers cable modem, use windows firewall and AVG Free.

My issue is this message I get informing me "16 bit MS-DOS Subsystem" on the top of the window in blue.  Inside it says

The NTVDM CPU has encountered an illegal instruction.
CS:0dc1 IP:0231 OP:63 75 74 20 69 Choose 'Close' to terminate the application.

I am under the strong impression that this is a virus, and am suprised that AVG is not able to detect / deal with it.  I am tempted to just delete the file, but I wonder if there is more to the virus than just this one small exe.

Can someone suggest how I should proceed in dealing with my current situation? 

Thanks for your time and help,



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    Re: Windows Error for "16 bit MS-DOS Subsystem"
    « Reply #1 on: April 11, 2009, 11:17:30 AM »
    You could try copying the files config.nt and autoexec.nt from c:\windows\repair to
    c:\windows\system32 and make them read only afterwards.

    I would advise you  to make backups of the files before you overwrite them or just rename the ones in c:\windows\system32 to configbackup.nt and autoexecbackup.nt

    Let us know how you get on...
    Custom I.T. Computer Services


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    Re: Windows Error for "16 bit MS-DOS Subsystem"
    « Reply #2 on: April 11, 2009, 11:54:41 AM »
    Most likely, you're infected.
    "16 bit MS-DOS Subsystem" message is often associated with malware activity.

    Read here: http://www.computerhope.com/forum/index.php/topic,46313.0.html
    Start new topic here: http://www.computerhope.com/forum/index.php/board,7.0.html
    Do NOT post any logs in THIS thread.


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    Re: Windows Error for "16 bit MS-DOS Subsystem"
    « Reply #3 on: April 11, 2009, 12:04:45 PM »
    Unless you have recently installed an older program designed for early ver. of Windows...
    " Anyone who goes to a psychiatrist should have his head examined. "