EMAPhil,
First, make sure that you've downloaded the most recent firmware from your region (Check the Samsung.com site, on the bottom of any page, make sure your country is reflected).
Next, the download is usually in a zip format. Make sure you unpack it to a freshly formatted thumbdrive.
Does that help?
--HDTech
I have not needed to upgrade before now but AVATAR finally made me.
My Firmware is BEv1.0-090327A-XEF
I loaded up the 2.12 software to USB.
Followed the instructions but got an error. The Samsung Suppport site has an announcement saying "early versions don't read a header....." Unfortunately the full thread does not open so I'm stuck.
Any advise welcome

Chowhound
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