I have had to reload my operating system twice in 6 months -- a real pain. How many others have had this problem? What do you do if this happens away from your home computer where you have BB Desktop manager?
I see from your profile you have the 9630. Which OS are you running? As far as needing BB Desktop Manager, it is the safest way to load an OS on your device. The reason is because you can back up your settings, apps, contacts, etc before you load an OS update. If you are going to update wirelessly, you run the risk of losing your data connection during download and risk bricking a Blackberry. BB Desktop Manager is the safest way to upgrade or downgrade. Let me know which OS you are running. Right now, I am running 126.96.36.1999 on my 9630 Tour.