What exactly does "factory data reset" do?

[mattmillus]

Hello,

I was just curious what exactly happesn when you do this. Does the phone tottally revert to the out-of-box state? What about your OTA updates to RC30, will they also be reverted back to RC19? Will setting changes you made to the OS be reverted as well? And what about your apps?

I just ask because I just got RC30 today and after download/messing with/deleteing a huge number of market apps in the first few days of having the phone I cluttered it up a bit and dont have a huge amount of system memory left. I would prefer to just start fresh and redownload the apps I actually want only. Thanks!

[JAWheat411]

It restores phone to the way it was when you bought it. You will have to setup your Gmail again. All updates should be gone. I did this once but can't remember. I just reinstalled the update from the SD card. Only took about 5 minutes.

[shookyang]

Why not just delete the apps you don't want?

[nickelleon]

Ive downloaded like 100 apps and im down to like 10MB of internal memory. I see a drastic decrease in performance and deleting the apps 1 at a time takes too long. I am in the same boat as the original post author and wanted to know about this as well.

I wanted to know if I could lose all my contacts? I came to tmobile from verizon and had to manually input all of them. This was 2 hours I would rather no repeat. If the contacts do get erased, is there a quick way to back them up and readd them after the reset?

I assume I lose my txt message history too?

[Geo411m]

This will remove all applications and settings. restoring the phone to original settings. It will not remove the update.

[G-won]

The RC updates will remain intact. Also, if your contacts is showing up in the "Contacts" list on Gmail due to synching, then you'll also be able to keep them after factory resetting.

[endmp25]

I really believe Google should make this function User password protected... because if anyone acesses your phone they can go in and "Default" your phone... and now my GPS tracker was meaningless... I would prefer my phone bricked if I lost it than have someone take it and sell it...

[mattmillus]

Thanks guys for helping me and nickelleon out. Its very good to know that I can format the phone and not lose the RC30 Update, as that was really my original concern.