We have seen some instances of various scanners unable to connect with their internal device drive due to a problem with Digital Signatures:
"Windows cannot verify the digital signature for the drivers required for
this device. A recent hardware or software change might have installed a
file that is signed incorrectly or damaged, or that might be malicious
software from an unknown source. (Code 52)"
It appears that a windows update has caused problems for a number of drivers.
Windows 7 users urged to uninstall broken update that wreaks havoc on software:
http://www.pcworld.com/article/2859120/windows-7-users-urged-to-uninstall-broken-update-that-wreaks-havoc-on-software.html
A fix is available here:
Install KB3024777 to fix an issue with KB3004394 on Windows 7 and Windows Server 2008 R2
http://support.microsoft.com/kb/3024777