Using UPK 3.1.6 and Windows XP sp3, all works fine.
when installing .Net 3.5sp1 the system would no longer work properly:
the red light status Red stays instead of becoming Green after the capture and we have to kill the application to exit.
I'm not sure why a .NET update would interfere with UPK 3.1.6. I suggest contacting Oracle Support to identify the cause of the issue. Please submit a ticket through My Oracle Support (http://support.oracle.com/)
UPK 11 has been released, if you want to try the latest version of the software.