What ports need to be allowed through firewall in order to access a remote machine via UNC file share?

Our TCOM team recently rolled out a new firewall which broke UNC access with machines on our internal network trying to access servers in our DMZ via UNC.  I was going to send a request to have these ports opened back up for a limited number of machines, but I can't seem to find a solid answer that tells me which ports are needed.  Do I need to allow ports 137, 138, 139, 445?  All of them, or only some of them?  Only from source to destination or both ways? Thanks!
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Here you have some information:


Mike ThomasConsultantCommented:
You will need to allow all of the ones you have listed both directions for the best results IMO.
Ports and an explanation of each, explained by microsoft.

Tray896Author Commented:
This is kind of what I was talking about.  I've gotten a few different answers in this thread, and can't seem to find an article that says "If you want to allow UNC access between 2 networks you need these ports opened in this direction."  Thanks guys. :-)
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