It turned out to be something very simple, but which wasn't obvious to
check to begin with. There was another computer (a Windows machine) that
was supposed to have been taken out of service a long time ago, but
someone has recently put it back on the network. Because it was supposed
to have been no longer used, it's IP address was re-allocated (a year and
a half ago!) to the machine that I have been agonizing over all week.
On someone's suggestion, I decided to put the problem PC on a different
subnet, because we thought it might be something amiss with the new
networking hardware that was installed a month or so ago, and suddenly the
problem went away. Some more investigation, and we discovered that the IP
address was still being used, and, thus, stumbled across the actual
Thank you to all who responded!
It's always the simplest things, in the last place you look...
Senior Computer Systems Administrator
College of Engineering and Computer Science
Wright State University
265 Russ Engineering Center
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