A few members have reported that sending private messages works strangely for them. On investigation this transpires to be due to the fact that their internet browser was blocking any & all 'pop-ups' and they could therefore not receive the 'Message Sent' pop-up.
Most website use pop-ups to provide help text, confirmation messages, error messages etc only the rubbish ones use them to bombard you with adverts.
We DO NOT USE pop-up adverts so if you are having a problem please check that your Internet Browser has NOT blocked all pop-ups OR (if you are using other websites which do use pop-ups to bombard you with adverts and so don't want to just blanket allow pop-ups) you can add us as a 'trusted site' in your browser (this Microsoft help note explains how to leave general pop-ups blocked but add individual sites as trusted - http://www.microsoft.com/windowsxp/using/web/sp2_popupblocker.mspx ).