I just ran into the PermGen version of this error trying to load the demo repository (demojuly2018share_v69.pprj).

The PermGen space is separate from the heap space. I had to increase that by adding the JVM option in run_protege.bat:

-XX:MaxPermSize=256m

It was an obvious problem in my case - I had run the Protege install as root, and therefore the Essential install couldn't write into it. Changed ownership of the Protege directory tree, and all is well again.

Hi Jonathan,

I'm having the same issue, even after reinstalling the Server components as you describe.

What could be going wrong?

This is on CentOS 7,

Thanks!

--rudolf