Hello Howard Miller,
Thank you for the response.
I have restored the 3.1 version but it does not log in normally. After entering the login details, it returns blank as before.
I used the debug url and I was able to set the debug on in the admin area. From their I could navigate to the course online but not the Dashboard, Site front, Notifications and some others.
This is the error returned with the blank page:
Fatal error: Out of memory (allocated 73400320) (tried to allocate 1110016 bytes) in /home/sites/..../public_html/..../lib/classes/string_manager_standard.php on line 138