Thanks in advance for your time and any help you may be able to offer me.

I have a MacBook Pro 2.5Ghz Intel Core 2 Duo running 10.5.6 that I used to be able to connect wirelessly [between Airport cards] to a Mac Pro elsewhere in the house - sharing screens, printer, iTunes Home Share etc.

This afternoon the MacBook Pro has 'lost' the Mac Pro [it doesn't appear under Shared in a Finder window and I can't connect via Finder -> Go -> Connect to Server].

An older [first gen] MacBook Pro of my wife's will connect successfully to the Mac Pro [it shows up in Finder and I can share its screen etc.]

I've installed no software, nor have I made any settings changes on any of the computers.

I don't have Time Machine on my MacBook Pro, so I can't roll it back to an earlier time to see if that solves the problem.

The airport on my MacBook Pro appears to be working fine [I can connect to the internet via my wireless router - that's how I'm posting this.]

The Airport on my Mac Pro is working fine, too.

But the 2 computers do not recognise each other.

I have: checked that File & Screen Sharing were enabled on both computers / repaired permissions / created a new user account on the MacBook Pro [same problem].

Do you have any ideas, please, as to how I can make my MacPro reappear in my MacBook Pro's Finder window [so that I can successfully connect to it.]

I have checked View options in the Finder, too

Thank you very much again!