You will need to be using an admin account for an install to work properly.

• Are you using an admin account in Windows XP when you get this update request ?
• What error messages are you seeing ?
• see also software Update Failed <-- clickable link

Thanks for your reply John99.

I am using an admin account.

I will try some of the other suggestions and let you know how it goes.

Hi John99,

I solved my problem by downloading the latest v6.0 Beta 4 update and installing/upgrading over my existing installation. That solved it!

Glad you solved the problem.

Not too sure what your v6.0 Beta4 is. My Beta channel install is only showing as Firefox 6.0
(Mozilla/5.0 (Windows NT 5.1; rv:6.0) Gecko/20100101 Firefox/6.0 ID:20110729080751)