After scanning a few fingerprints you may get an error indicating that you should Check to see whether the Device is Connected.
This is extremely rare. No specific cause has been found nor can we recreate this issue here at Gradience. We have found however, that if you're having this problem you can always work around it by closing and reopening Gradience TimeClock and it will work for a few more scans.
We apologize for the inconvenience.