Recently I had an issue where simply saving a tag from Mp3Tag caused major headaches with my MP3 player and Windows.
For whatever reason this only happened to certain Mp3 files - not all (in my case 100 of 400 Mp3's). The affected Mp3 files lost the ability to view or edit the tags from Windows Explorer (not really important to me), but it also caused my Mp3 player not to be able to show some tags, especially the album artwork (VERY important to me - actually the only reason I use Mp3Tag is to batch import the album artwork).
What was frustrating about this was the tags would show correctly from Mp3Tag, VLC, iTunes, and WMP. In fact, after Mp3Tag killed the ability to view the tags from Windows exlorer, if I resaved the tags from VLC it would "fix" the problem. Aside from tha tags issue the affected Mp3 files would play just fine.
The solution was to check the ID3v2.3 ISO-8859-1 box under the Mpeg Tags Write Options.
So I hope anyone else experiencing this problem can avoid the hours I spent finding this magic option.
I suggest adding a FAQ entry.