There is a simple short version too:
$regexp(%_folderpath%,\\The\s,)%_filename%
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Hmm, I don't think so ... the only thing that will make some trouble is ... how many other non music files are left in the old folder structure, which you have to move manually into the new (renamed) folders?
The forum contains an interesting thread about some experimental method to move non music files by Mp3tag:
Cover mit verschieben
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