Thread:Project:Support desk/Email function gone from toolbox after upgrade/reply (5)

It looks like none of the groups on your wiki have the sendemail right. Perhaps you've been overwriting your groups' permissions arrays, rather than adding to them?

The error message you were getting is rather misleading; that appears to have been fixed in trunk.

As a side note, you can get rid of the Newuserlog extension—it was integrated into the core.