I'll get some others to look at your problem. I am not a Vista or XP user, & only use Windows 2000 occasionally for testing purposes mostly.

My thoughts, if we can't find an answer is to try another p2p client for those accounts where LW is not working. Options are FrostWire or Phex to see if you have the same problems, are my recommendations. FrostWire is almost identical to LW. Phex is different, has some nice options such as size filter, but is not as easy to understand to use at first look; but I really like Phex. (What's more, you can even get direct help from the programmers in the Phex section on this forum, unlike the programmers of LW who now refuse to come here due to pure very unpleasant arrogance.)