Help me please.. How do i fix it
Go into your RO folder, into the Neoncube folder and open Neoncube.ini. This should be a word file (open with notepad or something.) Locate where it says patch_list in that word file. Does it say "patchlist.txt" in that row there?
Make sure your ragnarok online main folder didn't mix with other private server files.. xD
Actually, post the content of your neoncube.ini to make sure there's no mistake in it. Like LonelyBoy said, avoid mixing servers.