Magento

Hi Everyone,
I have just updated from magento 1.1.6 to version 1.3.2.2 it seems to have work but in the administration panel if i try to update anything one of two things happens either it will return to the dashboard with no changes happening or it will give the following error “Invalid Form Key. Please refresh the page.” which also means i cannot update anything on the site.

If anyone has any suggestions on how i can fix this it would be greatly appreciated.

Regards
Dean