Fingerprint Reader fails to execute.

For some time I have used the fingerprint reader with no problem. However,
lately problems have arisen. Possibly because of program updates that may
have created conflicts. When the problem occurred, I went to Control
Panel/Add & remove programs and "repaired", after which it worked for a
couple of times after rebooting. I have removed and reinstalled and the
result is the same. It works once after rebooting but after a seconf reboot,
fails. Any ideas?
--
Clem