Scanner buttons don't work

I've done lots of searching on Groups without any solution.

Windows 2000, SP4.

I have an Epson Perfection 3170 scanner. There are 4 function buttons

on the front that used to automatically scan, copy, etc. They

suddenly don't work.

I have reinstalled the scanner twice.

I have checked the settings in Control Panel/Scanners and Cameras.

I ran sfc /scannow to make sure my Windows system files were still OK.

I ran SysInternals Process Monitor. When I push the scan button, a

thread is being created for stisvc.exe. But all the thread does is

RegCreateKey, RegQueryValue (4 times), RegCloseKey, and Thread Exit.

The query values look right. They reference HKLM\SOFTWARE\MICROSOFT

\Windows\CURRENTVERSION\StillImage\Registered Applications\EPSON Smart

Panel, which I think is right.

I can give more details on the query Results and Details, if it means

anything to anyone.

I've been struggling with this for days. Any ideas?

Thanks,

Daryl