Actually, you did not need to go into 'dev mode' to use the T-Mobile sim to unlock the phone. Simply starting the phone with the T-Mobile SIM would have sufficed. Anyhow, what you need to do now, is start 'Device Info' -> 'Reset Options' -> 'Full Erase'. This should do it's business and restart the phone and will then give you the option to create a new profile or sign in with an existing one.
Originally Posted by fredflinstone1
Advantages of using a profile:
1. Purchase apps from the app catalog.
2. Backup of your call log/txt messages/contacts, email, & instant messenger accounts. This will allow you to restore your device in the case you have to doctor it and/or replace it. Also, it will restore your profile to another device that you may add later.
Bottom line, you do not want ot use the phone without a profile.