[TYPO3] Tools>Config+DBint (lowlevel) does not work after reinstalling

[Andreas Balzer]

Andreas Balzer schrieb:
> Hi!
> After i updated from TYPO3 3.8.0 to 4.0, i now had to de- and reactivate 
> the "lowlevel" ( Tools>Config+DBint ) extension. Well, after the 
> reactivation it just outputs "No handler found!!!" (without the quotes) 
> at startup. What should I do? I can't find the extension in TER2.
> 
> Please help me.
> 
> Andreas
ADD:
This problem does occur only, if i select "database relations" in the 
drop down menu. But then the whole module stops working for the specific 
user. The module works for the other users, as long as i do not click on 
that relation thing. Then it stops.. but for other users it still work..