You may have noticed that PMs are currently not working. This is a problem for the entire Invisionfree Server 10, and not an issue with this particular site. I've checked with Invisionfree, and they are aware of it, and currently working on it, but don't have a definite time as to when they might be back up. There was a similar problem on Server 3 as well, but that's already been fixed, so hopefully this won't be long.
Sorry for any inconvenience this may have caused.
EDIT: It seems that Invisionfree is busy with Server 6, which has completely crashed, so the PM system on 10 is a lower priority. The last estimate I was given was 'Sometime tomorrow, hopefully, or as soon as humanly possible."
So, there you go.