[limpet]

I had come to the same conclusion horndoctor, but once I was resigned to buying a new phone, I was willing to experiment.

Thanks rhacy, you are right...it's not the hardware, or at least not a permanent hardware failure. The phone is working now...fingers crossed.

I read the postings about XTRA.BIN earlier and experimented with what I think was a corrupted version, with no file at all, and with a valid downloaded version. This seemed to affect the behavior of the phone *after* the GPS had locked up, but not the locking up itself. I could make it crash after it got the first position fix or the failure I described in message #1. I could not, however, solve the problem by messing with the file or the QuickGPS registry settings. I'm pretty sure a cold reset installs a valid version of XTRA.BIN; a warm reset does not change the file.

All of this was done with a phone that had never been unlocked. Finally I unlocked it and flashed a different radio...that didn't solve the problem either.

Then I decided to try WM6.5 so I flashed a copy of OMJ_Diamond_Sense_2.1_23544_v1.2; still no joy! I love the revamped Diamond, but the GPS still locked up after the first position fix.

Finally I remembered that the last GPS program I installed before I noticed the problem was GarminMobileXTforWindowsMobile_50020w. So I tried installing that under WM6.5. After a few soft resets the GPS started to work again and all GPS programs functioned properly.

My tentative conclusion is that there is nonvolatile storage in the GPS hardware that is not updated when either the rom or the radio is flashed. It can be put in a state that will cause problems that are not fixed by a cold reset. I think problems with QuickGPS or other programs can put the hardware in the bad state. A corrupted copy of XTRA.BIN may be involved. I'm pretty sure that the reinstallation of MobileXT while a valid XTRA.BIN was present cleared whatever state the GPS hardware had gotten into and allowed it to be properly reinitialized by a soft reset.

The up side of all this is that I finally understand what all the fuss is about with upgraded roms...many thanks to all you cookers out there.