Error after downgrading to a prior version


After updating my site to I experienced some errors and therefore wanted to roll back my update.
After this I now can't enter my site and I presented with this error:

Class \Concrete\Core\Permission\Key\AddConversationMessageConversationKey does not exist

Does any of you know how to solve this error, so I can regain access to my site.
Any hints are most welcome

View Replies:
goodnightfirefly replied on at Permalink Reply
There is no rollback method I'm afraid, but you can replace the 'concrete' directory with the one from the zip. and restore the database you backed up before you did the update (you made a backup first right?).

Before trying to restore though, try copying the new files across again (or extract them again, whatever you did the first time).
tilde replied on at Permalink Reply
Hi - Thanks for your reply.

I managed to get acces by copying the file AddConcersationMessageConversationKey.php from another installation.

And Voila ! it worked !