iOS 5.1 Upgrade - Unknown Error (11)

[ParryD]

Hi,

I have a 3GS Factory Unlocked running on iOS 4.1.

I went for 5.1 update [Shift+Update] for the device but it stopped with the following error message:

The iPhone could not be updated. An unknown error occured (11).

On clicking more information tab in the error message was directed to the following page:

iOS: Resolving update and restore alert messages

The device remains in DFU Mode and get the following message on connecting to iTunes;

iTunes has detected an iPhone in recovery mode. You must restore this iPhone before it can be used with iTunes.

Got the device out of DFU Mode using tinyumbrella, again got the same message on updating.

I had updated my iTunes to 10.6 prior to connecting the device.

Pls assist resolving this error message.

 

[ParryD]

Disabled antivirus, used another USB port & tried doing a restore [shift+restore] but still no luck; got the same error message.