Mac to PC networking problem

[The Dude]

Does anyone know what ports I need to free up on the firewall on my PC so that I can access a shared folder from my Mac as an SMB?

It used to work before I put the (PC) firewall on, turning it off makes it work too but with the firewall on the Mac won't connect.

[mmm-five]

Try opening ports 137-139 on Windows to enable the connection.

[The Dude]

mmm-five said:

Try opening ports 137-139 on Windows to enable the connection.

Cheers.

Those ports were already open (as part of File and Printer Sharing) but had their scope limited to "Subnet". Changing this to "Any" fixes the problem but is this a wise thing to do i.e. leave thoes ports open to any TCP traffic? There's a hardware firewall on the router so do I need Windows firewall on at all?

[mmm-five]

You could always limit the machines that the router allows to the PCs & Macs MAC addresses only.

[cyberface]

You really don't want those ports open on Windows machines if they're directly facing the internet... however if you've got a NAT router blocking 135-139 inwards and outwards, you should be fine.

This should be reasonably easy to set up using 'filters' or 'rules' (depending on manufacturer) on the router interface (either web or command line).

Do take the time to set up blocks both ways though - you definitely don't want internet SMB traffic getting through to your internal network, but letting your SMB traffic leak out onto the internet can also be a problem (sniffing for keys)...

Edited by cyberface on Wednesday 19th July 18:46