Why does OS X Terminal say 'unknown:~'?

Question

When I open Terminal, it comes up with unknown:~ (user name) and will not allow me to do anything.

I haven't done anything to cause this, this is how the Mac started up.

Answer 1

The unknown: part of the prompt is your computer's hostname.

Os X sets the hostname in quite a complicate way.

1. The name provided by the DHCP or BootP server for the primary IP address
2. The first name returned by a reverse DNS (address-to-name) query for the primary IP address
3. The local hostname (set in the Sharing pane of System Preferences)
4. The name localhost

In the usual case, the hostname is your Computer Name as defined in Sharing-Preference Pane. You can change it at System Preferences -> Sharing -> Computer Name

I can't help you with Terminal being unresponsive at this point. Please provide more information on how things got this way.