If you run a FlexNet Operations Portal and it uses an Oracle database on the same Windows server, you may find that it fails to startup correctly when your host restarts.
The problem I found was that insufficient dependencies are set up between the two Windows services, and they get into a race at startup. The FlexNet service always seems to get there before Oracle, gets locked up and never recovers.
My fix was to add a dependency between the two services, using:
sc config FlexNetOperations depend= Tcpip/Afd/MyOracleInstanceService
This makes the FNO wait until the Oracle service is started, which has fixed the problem for me at least.
Note, you need to reapply this fix every time you re-deploy the FNO software.