SP4 MDAC NTVDM Error

I have SP4 on my machine. For some reason the first application I sent out
using ado has given me back a strange error about NTVDM - which if we go back
to Windows 95 days had to do with a command change (command.com). Is it
possible to see an error like this? I compiled an app that has run
consistently on an SP3 MDAC platform. I have compiled it under SP4 and
received this error.
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Regards,
Jamie
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