MTP driver file missing

System:
XP Home SP2, WMP11 installed
Device: Creative Zen Vision M 30GB

Problem:
I have had the Zen Vision M working for quite some time with my system. Last
weekend, I had a problem with another device, and the only way to fix it was
to do a System State Restore. It fixed the other device (flatbed scanner),
but broke connectivity to the Zen.
When I plug the Zen in, I get a message near the system tray saying "Found
new Hardware", followed by a message saying "Creative Zen Vision:M", followed
by "MTP device". Then I get an error message saying there is a problem. When
I open Device Manager, The Zen is listed under portable devices, with a
yellow error symbol. The properties box says "Reinstall the drivers for this
device. (Code 18)To reinstall the drivers for this device, click Reinstall
Driver."
When I click Reinstall Driver, it winds up saying, "An error occurred during
the installation of the device. The system cannot find the file specified."
I have reinstalled WMP11, removed and reinstalled the creative software, and
made sure the plug-and-play service is running. When the Zen is set to act as
a removable device, it does mount and transfer files, so it seems the
hardware is working, Problem seems to be finding the MTP driver.
If this is the problem, can this be found somewhere?