Dude First Download ""MP3 Player Utilities 4.00"" from here WWw.s1mp3.org/en/downloads_tools.php#top then..serch your Mp4 Software ver. and dowonload it from here.... wWw.s1mp3.org/en/downloads_fw.php I guess You need this...""LSD_501_10 SDK:V35.37"" but in place of it.. only ""LSD_501_05 SDK:V35.37"" there rest you easily find it there...what to do... Enjoy!!! arun

Though my SONY mp4 works properly,it generates problem with mp3 songs.Not all but some songs do not play and the same time player turns off,it restart selfly.I dont know why it happens.please specify me to my Id some websites wherefrom i can down load my upgrade version software. My mp4's version display following information. Lisong LSD-502 05 SDK:V35.37 2006-06-01