Windows Update Virus And Unable To Update

Hi - im having this problem at the moment where Bitdefender Antivirus 2010 displays it has blocked multiple virus attacks from windows update. It shows a long address running to a .cab file in the info bubble that appears but shows no virus name and does not treat or quarutine anything (download.windowsupdate.com/msdownload/update/software/dflt/2009/09/3023645_a88953b7b4d04d6d83164fa767d98a1771b70fd2.cab is the virus apparently)

Windows update is also unable to search for updates showing error message: Code 8024402F: Windows update encountered an unknown error and each time an update search is attempted the virus message is displayed again.

Any ideas how to solve this please as its quite annoying now and i cant update windows. Is it down to bitdefender thinking windows update requests are a virus or am i infected? A full system scan using bitdefender and other software shows my system is clean.

Thanks!