trouble installing Python-2.2a1.exe

[Tom Good]

"Tim Peters" <tim.one at home.com> wrote in message news:<mailman.995680776.21360.python-list at python.org>...
> [Tom Good]
> > I downloaded the Python-2.2a1.exe installer from SourceForge, and
> > verified that the MD5 sum is correct.  When I run it under Windows
> > 2000 Professional [Version 5.00.2195], I get an error dialog that
> > says:
> >
> > 16 bit Windows Subsystem
> >
> > The NTVDM CPU has encountered an illegal instruction.
> > CS:020c IP:0115 OP:0f 00 00 00 00 Choose 'Close' to terminate the
> > application.
> 
> [also Tom Good, later]
> > Sorry, I had thought that this was a problem with the installer, but
> > it really turned out to be a problem with my Windows configuration.  I
> > fixed it.
> 
> Would you please spell out what you changed?  I saw anther report of this
> symptom, a few months ago (w/ a different installer), but no follow-up.  I'd
> like to know how you cured it so we can help the next person who falls into
> this trap.

Searching around for the text of the error message led me to this:

http://support.microsoft.com/support/kb/articles/Q245/1/84.ASP

Which gave me the clue that maybe it had something to do with the
command interpreter command.com.  I fixed it by going into Control
Panel / System / Advanced / Environment Variables, and changed the
System variable "ComSpec" to point to c:\WINNT\system32\command.com
(it had been set to c:\WINNT\system32\cmd.exe).  Then I ran the Python
installer and it worked fine.  After installing Python, I changed the
setting back to the way it was before.

There may be other work-arounds or ways to address the problem besides
this, but this worked for me.

This link also has some info that may apply.

http://www.chami.com/tips/windows/122096W.html

By the way, the symptom of this problem was that I got the "NTVDM CPU"
error message immediately upon trying to launch the installer.  No
program window ever came up, just the error dialog box.



Tom