Thread:Project:Support desk/Mediawiki database error after update

I hope for some help on the problem I have trying to update my Wiki from 1.21 to 1.25. I don't have experience doing this but I followed the manual in Mediawiki.org. Create a new folder and put in the new fileset. Add the Images folder with content, moved the Localsettings.php from old to new. And renamed the folder to the right sitename. As result i get this: a database query error has occurred. this may indicate a bug in the software. I'm a beginner and hope for some help, I read some things about using command-line scripts but don't know how to do that, maybe I forgot something in this actions. I must get this update online soon because my hosting provider is going to use only PHP5.4 in 2 weeks what makes my current wiki stop working. Thanks in advance.