MultiWii

I'm getting the following error whenever I submit a post/reply:


The post get inserted but instead of a confirmation the above error gets displayed.

I know...
And I don't know what to do to correct this as I've no access to the installation repository of this forum.
(it's an automatic install from the web hosting provider with limited file access)
I plan to migrate it one day on the main site (www.multiwii.com) so that I can have access to all files.

are you able to backup the database? If you want I can setup a phpbb site on my server.