Remote PC showing as offline when it's not

[VBScab]

This is bizarre...

When I start a TV session on my laptop (let's call it PC1), one of the remote PCs (PC2) is showing as offline. However, when I use the remote PC (PC2) to TV to my laptop (PC1) - i.e. going in the reverse direction - and start TV then, the remote (PC2) is listed, obviously with the suffix "(this computer)". It also shows as being available when I look via the TV management console.

To my mind, this wouldn't be a firewall issue or I wouldn't be able to remote from PC1 to PC2.

[matt]

Could be firewall, the connection is a different port to the 'heatbeat'

[VBScab]

Thanks for that. Any chance of a clue as to which port might be being blocked? I've read in many places that, provided you can browse the web, TV can get in and out. Is that not the case?