Right in between Profile and Logout on the main links at the top left is a space and if I hover over the space I see the text ".../forum/index.php?action=pm". This leads me to believe that right there (where there is no text) there should be text maybe saying PM? or something. Any ideas as to how to fix this?
Btw I tried to search but search is currently down. =(
If you are using another language than english it might be that the translated string is missing - or the translated graphic button. It depends on which SMF version and theme you are using.