The Samsung tech you are asking for (Samsung_HD_Tech) is out for the week, so to get an answer from him, you will have to wait until next week. Looking around on the Greece Samsung site, it looks like your TV has Wiselink Pro. But, I can't read greek, so, I might be wrong.
Make sure to post the details about what is happening (or not happening). Post what type of file you are trying to play.
Make sure the USB stick you are using is formatted with FAT16 or FAT32. NTFS file system is not supported. Also, I do not believe external hard drives are supported, so, make sure you are using a USB "flash" memory stick.
This link: http://www.samsung.com/gr/consumer/learningresources/tv/mediasolution/wiselinkpro_usersguide.html
should give you the supported file formats for Wiselink Pro on the Greek website.
Hope this helps.
Please look in my thread, if you can help me!!!!
http://forums.cnet.com/5208-13973_102-0.html?threadID=333934
Thanks

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