I am a Support Engineer with Xerox Scanners.
After reading your comment, it is clear that the issue you are having is not due to any hardware failure of the Documate 515. Being that the scanner works on another computer, we can rule that out as a possible issue.
In your comment it does not state how you determine that the scanner is not being recognized by your computer. Assuming that the scanner does not show up in your device manager, here are some suggestions to get it to communicate with your computer:
We also have an extensive support site and knowledgebase at http://www.xeroxscanners.com/en/en/support/
If you continue to experience trouble, please feel free to contact us by calling 800-648-0410.
Xerox Scanners Support
I installed a brand new Documate 515 over three months ago on my Windows 7 Pro Dell desktop. It was working great but suddently it stopped working. My computer does not recognize it anymore. I have uninstalled and install the software without any success. I have used every single USB port on my desktop w/o any success.
I hooked up the same machine to a different computer using Windows 8 and it works on that machine.
Any suggestions to get it working on my Windows 7 machine are appreciated.