I have this issue sometimes. In most cases I've found that deleting the TV3E database does the job. I don't know if it is the connection to M$ SQL server that is the problem, or if the db gets corrupt. Having TV3E start from scratch seems to cure the problem though.
A while back I did an export of all channels, maps, and groups in TV3E so I can just import that rather than rescan etc. If you use the excellent TVScheduler from dvdfreak you don't have to worry about missing recordings either because they are recreated once TVScheduler connects to TV3E again, and with the TV3E recordings importer the problem with old recordings is solved too.
I've encountered this similar problem with SVN 17915 till the latest one. It is simple to reproduce:
- install TVServer with more than one tvcard, make sure everything is working
- yank one tvcard out
- et voila, setuptv is going nuts, while the tvclients still seem to work
Very frustating... adding tvcards seems to be no problem, but removing them causes the problem.
Deleting the database in SQL fixes the problem, however this is no real solution (not fun losing all the channels etc.)
I can confirm I experienced much the same with TVE3 18436.
It was caused by updating the drivers for my Win-TV HVR-4000s. I guess maybe TV Server saw them as new cards. It allowed me to launch the configuration program once but said it could not connect to the server (even though it is a single seat installation). Rebooting did not help. Dropping the database and then restarting the configuration program resolved the issue.