Why do most files say invalid file format when I try to open them

Did you uninstall or upgrade or update suretrack?

This may indicate that the file extension is not recognizable.this may be a flac or orb file instead of the usual file formats associated with audio codecs these will need to converted into mp3 or wav etc. by using an audio convertor program...freeware can be found online.if your media plays only mp3 and you try playing different file extension you will get error.so you need to convert all your music into mp3.Itunes has a built in cd ripper to convert into most formats.

Check the TV manual for which movie file format will run from the USB port on the TV.
You may need to convert your movies to a file format the TV uses.
Check out this WEB site for video file conversions.
http://www.fixya.com/support/r5874192-play_videos_mp3_player

Without a specific description of the file format or file size limit, a good way to test what works is to create some very short files saved in different formats on your PC then load them on your memory card to see which ones work. Usually formats like .WAV, .SND, and perhaps some others may work. They can be easily saved to test on your PC.
The main SAVE AS considerations are:
Extension;
Format: as in PCM, and about some 18 others; then
Attributes: frequency, bit-rate, and Mono vs Stereo

Windows basic sound Recorder will let you load a sound file and save it in different formats [with some limitations] but enough to experiment.

well.. might b bcoz of virus.. jus do a hard reset and format ur card again n now fill ur stuff.. ( if u've mentioned ur mob model means it'll would be easyier to answer n i would've given u d reset codes.......) any how, for nokia *#7370# s d general reset code.....

it means tha the computer isnt able to put it on your MP3 or play it.

Hi,

It may be that excel file saved on your thumb drive is in .xlsx format(Office 2007) which you are trying to open on a machine which doesnt have office 2007 rather it may have Office 2003 or lower vesion.
Check this and hope it helps !!
Awaiting response.
Thanks !

maybe the file format has been changed ! try to manage those file format in your file manager

Because Micorsofts media player has a limited amount of file types that it will play. An option is to use some other player such as realplayer. Another option is to obtain software that will convert one file type to another.. I am guessing that you have the most update  media player. If not , download in through windows update.