CI fails to create session

[eluser]zsela[/eluser]
@Denis Molan: now I use CI 2.1, no HMVC and no custom session class, just the CI default. I didn't try to use a custom made session class yet.

@InsiteFX: as I wrote before, the whole CI session handling was working one day, but on the other day it didn't. Perhaps I made some changes in the code (maybe accidentally) which ruined the working session handling.

I guess I have to download an unspoilt CI package and try if that works. Then I can put my own code into that step by step.