8120 won't update from 4.3.0.115

I just bought a used, unlocked 8120 that began its life as a t-mobile phone. I am a t-mobile customer currently, if it matters.

I downloaded the blackberry software to my windows xp pro laptop to try to update the phone software, and no luck. I run the software, and it connects to the phone and then states that I am already running the newest software.

Is the software versioning different for the AT&T network than what is available on t-mobile? Or is there something I overlooked?

I followed the link in the sticky thread for the download, but that page specifically mentions AT&T.

Any ideas?

Did you delete the vendor.xml file since you are with Tmo and you are trying to use at&t OS?

Did you delete the vendor.xml file since you are with Tmo and you are trying to use at&t OS?

I didn't try using the download yet, as I wasn't sure if it would work (due to the difference in carriers). Instead I tried running the update process through internet explorer, and the application that comes from that method declared that my software is up to date.