Ah ha!! Thanks to persistent searching, I found the solution. It has
nothing to do with previous registration edits, those don't exist.
What I did was search in "Classes Root" for mp3 as a key, and find any
"EditFlags" value - change whatever is 01 to 00 - I did this for every
one that I could find, opened IE again and it worked!
Change MP3 to whatever file name, and you've got a solution.
Stupid thinking for Vista to do this but eh... everyone has their flaws
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andsoitgoes