No expert myself at all, but looking at the post in another forum below, it seems it might do the trick;
http://www.dvinfo.net/forum/archive/index.php/t-14078.html
Change the extension from m2t to mpg and it works in WMP, at least it did in WMP 9.
Why not try it. Make a copy of the file, (never test on an original), change the file extension on the copy, and see if other media players can play it, and at what quality.
Whether that will work for YouTube I can't say. Perhaps YouTube has a help page for uploading files.
Mark
I've been struggling along finding an editor for my .mts AVCHDlite files from my Panasonic FZ35 up to youtube in it's best format.
I am now working with Sony Vegas9 and have managed to build a movie about 7 minutes long and about 1.1 gig in size @ what I believe to be it it's best filetype as described as mpeg2 (720P) but vegas gives it the m2t extension which youtube is rejecting. What are my options to get it packaged and accepted.
this is the statement the program provides about the carrier(?)
Audio: 384 Kbps, 48,000 Hz, Layer 2
Video: 29.97 fps, 1280x720
Use this setting to create an HDV 720-30p MPEG-2 file with .m2t extension.
the only diiference I see from the original is perhaps about half the frame rate, and the m2t extension.
Can I just rename the extension? Youtube says it likes mpeg2, but won't take this m2t file, or at least a file with the m2t name.
or
Should I just dump the Sony trial and move on to something else that will work without this issue?

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