Consider the following scenario:
o On a Windows Server 2008 or Server 2008 R2 machine, uninstall a WIA Scanner driver via Device Manager
o Then in Device Manager you “Scan for hardware changes” or restart the computer to install the scanner again.
When you try to install the scanner again, the Administrators group does not have permissions to modify the registry key:
Since the Administrators group does not have permissions, the DeviceID in the registry gets incremented after the reinstall finishes causing a mismatch of DeviceID registry keys.
To work around this issue, grant the Administrators group “Full Control” of the StillImage registry key. Once the Administrators have permissions to modify the registry key, the DeviceID will remain the same after uninstalling and reinstalling the Scanner.
for other considerations.