Why won't my Bravia KDL37EX503U play mp4 files from BBC I-player via memory stick?

[beano16]

Hi all - new to this and not very technical so forgive if I don't see the obvious.

My family and I want to view some BBC programmes that I've downloaded using BBC I-player. We can't all sit round the computer monitor so I thought ah hah they're all in mp4 format  so easy... download them from my computer onto a memory stick, shove it into the usb slot on the Sony Bravia and bingo we can watch them on tv!

Sadly, all I get is the message "Playback not available". Yet the TV will playback other mp4 format vids that I have (albeit without sound).

Any thoughts please?

[beano16]

Hi  Bernie and thanks this is really helpful... will give it a go!:smileyhappy: