[HELP]317 Delta Problem

[Danielplanto]

I used to run my server fine, then I got a new computer and am now running the server. When I connect, everything is OK. But when my friend tries to connect, via Hamachi, or my external IP, I get this error message:

Connection from HEATHERBATCHELO:62505
Connection reset
java.net.SocketException: Connection reset
        at java.net.SocketInputStream.read(Unknown Source)
        at java.net.SocketInputStream.read(Unknown Source)
        at client.fillInStream(client.java:14554)
        at client.run(client.java:23815)
        at java.lang.Thread.run(Unknown Source)
ClientHandler: Client null disconnected (HEATHERBATCHELO)

Can I get some help please? Recent changes to server include adding a new Donation Skill -- Levels up and adds an exp bonus. Levels up when you donate, $1-1level. Max level is 150 for all skills and has been even when the server was bigger with more people.

Please help me?

Daniel

PS Need anymore info, just ask.

Friend in same state as me(Nathan): Ran it, logged in well.
Friend in diff state(Billy): Ran it, had this problem

Both have JRE7 in Program Files(x86)\Java

I dont understand why Billy cant connect. they both downloaded the new client.