It depends on if you have any problem with the phone, like battery problem, not working to charge etc. Then you should restore the iphone. If you don't have any issues like these then it's enough to restore your iPhone at least once a year.
Plug it in to iTunes, press Restore. It should restore your iPhone to its factory settings, thus killing the jailbreak.
You have to hook your iPhone up to the computer you last synchronized it with otherwise it won't restore.
If you want to restore your iPhone plug it into the computer, open iTunes and click the restore button. You will lose everything if you don't chose the correct backup.
Simple, plug into iTunes, restore to factory settings.
No!
Your not supposed to restore or update anything after jailbreaking a phone.. it messes it up. They should have told you that when you got it jailbroken
Easy! You just connect to your computer, make a backup, restore to factory settings, restore from backup, password gone!
No, I jailbroke my iPod touch with blackra1n, and I didnt have to restore it.
Not at all! Even if you end up jacking up your phone you can always restore from iTunes!
You can restore it using itunes. You have to get the phone into restore mode first. Open up itunes on your computer. Plug the usb plug into the computer but dont plug in the iphone. With your iphone powered OFF, hold down the home button and plug the iphone up at the same time. It should put the phone into recovery mode. The phone will say "plug into itunes". Then itunes should recognize the phone in recovery mode and ask if you want to restore. If it doesn't work the first time keep trying holding down the home button and plugging to the computer. You should try and find the owner of the phone or turn it in to the cell phone company so they can return the phone to the rightful owner.
click on Restore in Itunes
Yes, you will.