AT&T has finally rolled out Over the Air (OTA) update of  Android 2.2 Froyo FRF85 build to their customers who own Nexus One. Its a gradual roll out of updates so those of you who haven’t received it yet don’t need to panic, you will soon receive a notification.

In order to access the update, you will receive a message on your phone’s notification bar. Just download the update, wait for it to install, and you should be all set. This update will be rolled out gradually to phones – and most users will receive the notification by the end of the week . We hope you enjoy these new features.

If you have rooted your Nexus One with custom ROM, then you won’t receive the update. You would be required to roll back to the FRF50 or FRF83 in order to receive one. If you are not interested in it then you can always check out our post on how to update Nexus One manually.

Update using official patch file
You must be running the stock FRF83 release with stock recovery. Copy that file to the root of your sdcard, rename to update.zip, launch recovery (power on with volume down held), press power and volume up when the warning triangle icon appears then select ‘apply update.zip’.
Download: Google

Update.zip to flash with custom recovery
This is the totally stock FRF85B repacked as update.zip. The radio hasn’t changed since FRF50, so if you are using it, you can keep it and install the noradio version.

Download:
- without radio image: Download links (md5sum: 239237c5d59ba14d50ca4c3e614e0e13)

Root
To root FRF85, just flash this update.zip (df9bac43866eb048479fa16fa1b559dd) (contains busybox, superuser.apk, su, unsecured boot.img)

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