Problem Description: I have Windows XP Professional – Service Pack 3

I am unable to run a backup using Windows Backup Utility.
Start – All Programs – Accessories – System Tools – Backup

The Backup Utility start screen will partially show on the screen; however,
the program will never run. I have left this running all day and I never
actually get to an opening screen.

When I start Windows in SAFE mode, the same procedure works just fine. The
backup program launches and automatically goes into wizard mode. The problem
with SAFE mode is that I am unable to choose an external drive as a backup
destination.

Since this program does run in SAFE mode, I assume that a third party
software that is running is preventing the backup program from launching
successfully.

How do I identify what is causing the problem?
Operating System: WindowsXP