one machine can login via SSH tunneling, one can't

Hi there-

I'm afraid I'm totally baffled by this. I have the same recent build of HeidiSQL installed on my notebook and my desktop, both Windows 7 x64. One of them is able to connect through SSH tunneling, one of them gets error 2003. They're both on my home network, the server has both pubkeys, the SSH step isn't what's failing, and the error message implies that it's logging into MySQL that's giving my trouble.

Any thoughts? I appreciate it!