Phone not switching on after a system upgrade

[MIZXR6]

My other half upgraded his phone today via WiFi. After switching the phone off then on, it won't go past the "S" start up screen.

Somebody please help!

[Richardj]

Power the phone off, if you have to pull the battery out for a few mins and then put back in. Try and start the phone. If you still get the same problem you'll need to do a wipe data/factory reset.

To do this:
Power phone off(if needs be pull the battery out and replace)
Press and hold the following keys: Volume up + Home(the bottom middle key) + power.
When phone boots to the Samsung Galaxy S screen release just the power key.
When phone boots to a screen with lots of coloured text, release the other keys.
Look for wipe data/factory reset, use the Volume up/down keys to move to wipe data/factory reset, then press the power key to select the action.