I have login/logout problem also ı realized that my cache folder is empty.İn my site there are a general cache problem.Please help me!
Check the prmission settings on the cache folder.
I check all of it but they are true.There aren't any problem about permissions.
What ftp program did yoou use to upload the files?
It's possible the cache folder was uploaded in the wrong format. Try re-uploading it making sure it uploads as ascii format.
If you have safe_mode enabled this can be a problem.
I use Filezilla.How can ı sure filezilla uploads as ascii format?
I use joomla also so safe mod can't be a problem.
I guess you can ignore what I'm telling you even though I've had the exact same problem. But hey...wtf do I know?
I talked before with my server administrator and they disable safe_mod.
They should, but try reupoading the cache folder and see if that fixes the issue.