Which version of Lapper are you using?
Did you modify anything on the Default Lapper script and if so, try it with the default file to see if you still get an error.
1: the server is not in my computer, so i will ask playchicco if it is ok.
2: we tried in vista and xp too. i think in xp its sp2, but Playchicco will know this
3: we tried with .NET 2.0 and 3.5 too...
thank you your reply, but still not works... any other idea? maybe its not a lapper problem, cause in my computer, the same instance is working, but in the server its not ok...