There are a few different issues that can arise when installing an HP Scanner on our Windows XP image. These issues and their solutions are listed below.
The Wizard relies on the TWAIN drivers and other universal support files that the HP installer puts on the system. Without these files, the Wizard will not recognize the scanner. However, as long as the HP software is resident and functional, the buttons on the front of the scanner will activate it and produce an error message.
The workaround for this part of the issue is to install the HP software, test the Scanner and Camera Wizard to be sure it recognizes the scanner, and then disable the HP software without uninstalling it.
The particular filenames aren't a known commodity, but what has worked in the past is to delete all of the .exe files in the HP directory. Once that's done, re-test the buttons to be sure they don't activate any of the HP software. If they do, use the Task Manager to find the name of the executable, and then delete it. Repeat as necessary.
Once the HP software has been disabled, you should create a shortcut to
the Scanner and Camera Wizard in the Applications folder on the Desktop
and rename it to "Scanner and Camera Wizard" or something meaningful. The
path to the Wizard is:
    c:\windows\system32\wiaacmgr.exe