When you bring up the Bitdefender interface in Advanced View and try to change anything in the Antivirus->Shield tab you may see a message saying that the Realtime Protection is Unavailable.
In order to fix this issue please download
this patch and run it on your PC. The patch will stop all Bitdefender services, replace a missing or corrupt file from your Bitdefender installation and then restart the Bitdefender Services. After the patch finishes please reboot your PC and then open Bitdefender to verify that the issue is solved.
Applies to: Bitdefender Antivirus 2009, Bitdefender Internet Security 2009, Bitdefender Total Security 2009
Operating Systems: Windows VISTA, Windows XP