Thread:Project:Support desk/Fatal error: Class 'MonoBookTemplate' not found in.../reply (6)

When you say that you followed Manual:Moving_a_wiki, how have you installed the files of your MeiaWiki version? Have you taken them from a tar archive, which you had created before? Or did you download a new version from mediawiki.org and used that one?

Having a look at the 1.24 version of the Modern skin, the class ModernTemplate is defined in SkinModern.php, not in Modern.php.

Are you maybe still using old skin files, which cause trouble? See Manual:Upgrading!

Please make sure that
 * a) the right files were extracted on the new server and
 * b) all files were extracted.