Can't connect to buddy

[Butch]

I have installed Pidgin 2.10.9.
  - Windows Vista :-(
  - MSN protocol

I see former contacts from our old MSN messenger, but it shows all as 
"Unavailable".
One of those contacts is here in my house.
On that system:
  - Windows 8.1
  - MSN protocol
My Buddy icon shows up and it says I am "Unavailable.

Now what do I do?

Thank you