[TYPO3] cannot update / insert content element

[Dominik Funk]

hi,

first, sorry for my bad english ;-)


i have a strange problem...

from one second to the other i cannot insert or update (some elements) 
in typo3 4.0

first this problem occured on my live linux environment. now i have it
also on my windows development platform.

typo is correct configured an i added a lot of content elements. without
a change to the config i cannot add a new content element any more.
i can also only edit some elements but not all.

i add or edit some text in the rte editor then i press the save button.
the page reloads an all my changes are gone...

i am admin user an typo shows me full rights...

does anybody have a idea?

thank you very much
dominik