Installing Javascript Transformation leads to "Internal Server Error"

I’m busy to install and configurate the system and some parts are working. The binding to my knx-bus and binding to my yamaha avr.
But after installing Javascript Transformation from the Paper UI I always get an error “500-Internal Server Error” on Paper UI. And the HABPanel shows “Connection lost! Trying to reconnect…”

Restart doesn’t help. What can I do?

  • Platform information:
    • Hardware: Raspberry Pi 3, 1 GByte
    • OS: openHAB 2.1.0-1 (Release Build)
    • Java Runtime Environment: which java platform is used and what version
    • openHAB version: 2.1

I just typed this up. Come back here if clearing the cache and tmp doesn’t fix your problem.

I have now stopped OH, cleared the content of cache and tmp and started OH again:

sudo systemctl stop openhab2.service
(Cash cleared)
sudo systemctl start openhab2.service

The result is, that habpanel is not working and on PaperUI-Configuration-Items no item is displayed and “ERROR: 500 Internal Server Error” appears.

In openhab.log are no errors after startup. When Stopping, there are several errors like this:

2017-11-21 17:34:24.584 [hingStatusInfoChangedEvent] - 'astro:sun:local' changed from UNINITIALIZED to UNINITIALIZED (HANDLER_MISSING_ERROR)

Edit: ERROR 500 is a new error. Clearing the cache was the solution of “Internal Server Error”. Thanks!

I’m out of ideas. Usually clearing the cache will fix 500 errors, not cause them.

I did the stop, celan and start -> did not help.
Now I need to go to manual clean but see following structure:

removing /cache folder and its content or only content?
removing /.cache as well?

Is it save?

After several tries to clean the cache and few clean reboots I was forced to use my backup. The SD card was damaged probably. Coming back to the 2.4.x version and upgrading raspberry pi with all packages incl. grafana and openhab itself, system came to alive. Since couple of days it is running.
Thank you all for hints. Will use them definitively in future updates.