Try a tag editor if you must do this. Yes, might be a bug but XP bug fixes are not going to happen.
Running Windows XP, SP3. I have noticed that when I try to edit an id3 tag on an mp3 using Windows properties, when I try to edit another field (like genre or song title), I end up getting a strange character tagged onto the end of the Artist name and I have to manually delete it. Why does this happen, and is there a way to prevent it?

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