Folder Not Writable after installing theme but permissions set to 777

[Domi]

Hi,

I have installed getsimple and tested some themes without problem, all is working fine.
Now, I'm trying to install Grill theme and template (http://get-simple.info/extend/theme/gril...-site/873/), when I try to login as adin, the install seems to be back and I get a message that the folders /data and /backups are not writable although I have put all to 777 (tested 755 without effect); any help please ? - strange that after installing this theme, the error occurs and not with the other ..

Thanks in advance,
Domi.