[SOLVED] ERROR:500 internal server error when adding a channel to generic mqtt thing

Hi, im trying to add a channel to a Generic Mqtt thing that already has channels. Everytime i try to add a channel i get a ERROR:500 internal server error.
Any ideas?
All other channels/items work as expected…

Can you post what channel you are trying to add as well as the error logs. Thanks

I am trying to add a RSSI Channel for the wireless %. Just like the shown WifiSSid Channel allready there. I dont have any error logs. From teh Openhab.log i have this line:
2019-11-14 17:25:28.597 [ERROR] [ersey.server.ServerRuntime$Responder] - An I/O error has occurred while writing a response message entity to the container output stream.
Followed by a lot of other stuff, that could be in the timeframe when i tried to add a channel.

Where can i find or activate an error log. then i would try to do the same thing again and see what happens

I have the feeling that somehow i missed something when creating a channel…Is there something that needs to exist, befor adding a channel? and using that Id or something that a channel can be created?



just tried again and the channel is created…maybe i used the wrong syntax or something.
V, thnx for the help. Will post if the problem occurs again.