Problems w/ Apache & Vista Ultimate

At some point between mid-November and today, Apache stopped working on my machine. Whenever I try & manually start Apache, i see the following message in the System log file:
The Apache2.2 service terminated with service-specific error 1 (0x1).

Does anyone have any idea what could be causing this error? I could re-install Xampp but would like to avoid it if there's a way to resolve the issue otherwise.

 

Giving Up

To bring everyone up to speed, I have done just about all I can.

• Checked for Port 80 conflicts
• Checked for other apps that might be listening
• Uninstalled/Reinstalled XAMPP (Twice!)
• Edited hpconfig files
• Disabled/Enabled Services
• Restored old registry settings
• More things than I can remember

The upshot of all this is that nothing changes.

I believe that something has gone south in my Vista installation because a few other things like IrfanView won't work. Unfortunately, there doesn't seem to be any common thread here.

Oh well, on to IIS.