Hi, first time reporting something so hope i'm doing this correctly.

If you set a group 'Newly registered users' for example, so that they can not use the PM system at all (All permissions to NEVER) You can still actually see the links and icons around the forum (view profile/ view topic etc) to send them a PM, and when used...the PM is sent to them. Also the notification emails are sent, telling them that they have a PM.

Seems that the PM links around the forum shouldn't show in the first place for groups/users who can not read/use the PM system.