Computers randomly being droped form the domain?

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haveing random computers on my network being droped from the domain,
figured out what the problem is of what is droping them (some how the
TCP/IP drivers are being deleted, but they are still showing up, but
all i have to do is reinstall them and it reconnects to the domain..)
but my question is Im trying to figure out why the tcp/ip driver is
being removed from random computers, and what are somethings i can
check to troubleshoot the issue..

useing windows server, and windows xp and 2000 machines..

any help would be appreciated

thanks
brad

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