Can't join friend's server

[wfi974]

Title: Can't join friend's server

Version: 3.0.3/3.0.4

OS: Window 7 Home Premium x64

Java Version: jre6

Description of Problem:

When i tried to join me friend's server, this constantly pops up:

Internal exception: java.lang.NullPointException

(note this did not crash my MC, but i cant get on the server)

on my friend's side:

sending serverside check to: wfi974

and then:

wfi974 lost connection: disconnect.endOfStream

Error Messages:

http://www.pastie.org/pastes/4172638/text

Error Log:

[wfi974]

i just installed both 32bit and 64bit Java 7u5, but it still wont work D:

[wfi974]

Hello? I still need help

[wfi974]

ok i fixed this by watching a youube vid:

the host needs to delete the user data of the server from the players file in world

its easier than i thought :P