Impossible to save new page: redirecting to site root

[earlyriser]

Hello.
I have installed the 1.7 version in a subfolder. The Health check is ok and I have turned off pretty urls,all of the data folder are set to 777. However everytime I try to save a page I get redirected to the site root. When I try to upload a file I get a IO Error - .

GS is installed in a subfolder like domain.com/cms

Any help would be appreciated.

[ccagle8]

hhmm, is there anything in the errorlog.txt file in /data/other/logs/ ?