Foren / Cotonti / Support / pfs messed up

my pfs on my website is all of a sudden messed up, i have no idea how this happend....

yesterday i installed the fkceditor plugin, but i dont recall doing anything with the pfs....

i can still upload files in the folders i already created but i cant create any new folders either

this is how it looks like now:

http://www.cotonti.com/datas/users/pfs_297.jpg

Added 7 minutes later:

oh i found the problem.

i use the watermark plugin, and in the config of the plugin i got rid of the .gif extension....