Something is stubbornly blocking ports
The ports are 51413 and 54631.
I have tried connecting via aiport and ethernet. Different ethernet cables tried.
I have tried a variety of different IP address, to check if a certain IP is having problems for some reason.
Firewall is off. Anything else that could possibly need to connect to the Internet is off.
I have repaired permissions, etc, and used the combo updater to reinstall 10.6.4.
I really have tried everything I can think of, but this darned Mac Mini Server just refuses to open those ports. The only thing I can think of is a problem deep withing the OS, but I would have thought reinstalling the 10.6.4 combo updater would have resolved such an issue.
51413 was open until quite recently, but now although I can download torrents, I can't seed them. 54631 is for Air Video Server, which I tried to get working recently, and had no luck.
There were no obvious events or causes for this Mac to behave like this, so I am hoping that someone can help me troubleshoot this issue.