I have just installed an old Moodle and then a completely new Moodle on my server. Both versions have the same problem:
My strings refuse to display. Instead I see the names of the strings (in between double squares). This even goes for the install script.
I have checked the permissions of all the directories (and set them all to 777, just to check that that could not be the problem) and the dirroot and so are okay. All the language files are present in the normal location.
Are there any other things (server/php - settings) that might cause this strange behaviour?
I will give the solution to my own problem for anybody that might encounter the same problem in the future.
In my php.ini file there was a reference to an Ioncube accelerator zend module. Disabling the loading of this Ioncube module solved all my problems.
In my php.ini file there was a reference to an Ioncube accelerator zend module. Disabling the loading of this Ioncube module solved all my problems.