I finally got rid of one instance of Twain Tech on an XP machine after
days of fighting it.

1. I deleted everything in \documents & settings\*username*\local
settings\temp folder.
2. I deleted the key: HKLM\software\microsoft\windows
NT\currentversion\winlogon\notify\WPAEvents. It was pointing to the
"2ldsrch.dll" file in system32 folder that kept coming back.
3. I ran the Giant software that finds and deletes the "2dlsrch.dll"
file that shows up as 'TwainTech'.
4. Reboot

If you update to Windows XP service pack 2 and run the "critical
updates" for XP, you can prevent programs like this one from coming
back. I just wanted to see if I could get rid of this one manually
before updating to SP2. Hope this helps someone! - Jim
http://www.wwwdothttpdotdotcom.com