I have a Blackberry 7520 with Nextel and BlackBerry desktop software 4.2 SP2. There appears to be a conflict with the Vista OS. I've worked with Microsoft Tech Service for some time to isolate a "Failed to start" problem requiring recoveries on many occasions. I've performed several clean uninstalls and reinstalls of the BlackBerry software with no improvement. The computer is fine without the BDS, but has problems whenever it is installed. I really like the phone because it is very durable and I work in the field quite a bit, so getting a newer version is not an option (other field people have had durability problems with thier newer phones). Any ideas?