How do you unjailbreak a device?

Answer 1

Connect it to your computer and make sure it's synced and backed up. Then, hold the home and power buttons and count to ten. It should look like it's off and it will disconnect from iTunes. Then take your finger off ONLY the power button and continue to hold the home button (will take a while) until it reconnects. It'll show a generic iPod in iTunes, so hit the restore button. Wait. Then once its done resetting, sync it to your last backup.

Answer 2

Assuming that you are referring to an Apple Mobile Device (iDevice), here are the steps:

To unjailbreak, you will have to restore your device to factory settings

1. Open iTunes and, plug your iDevice into the computer.
2. When iTunes detects your iDevice, a new page should show up with different options. If not, go to the pane on the left, and select your iDevice (shown under "Devices").
3. By default, it should be on the "Summary" tab, if not select it from the top of the page.
4. Click the "Restore" button.
5. Wait until it is restored and rebooted.

*This requires internet access.

**Do not use Mobile WiFi hotspots / tethered internet from a cellphone. It will be slow and you will be charged a lot of money if you don't have a data plan.

***Please note that if this is the first time restoring to a firmware, it will download around 0.6 - 1.2 GB of data. Make sure you have sufficient bandwidth and speed.

Answer 3

Connect it to iTunes and click restore.