Access UNC path from Internet?

no b/c the protocols that are required (such as netbios) simply aren't allowed over the internet.  In addition, there is no regulation of UNC names on the public internet like there is with public DNS, so if you try to access \\server\share\ over the public internet it wouldn't work b/c there would be thousands of hosts with the name 'server' and the requesing pc would have no idea which was the one you wanted to access.

the only way to really do it would be to have a VPN tunnel between the two machines.

What if that server has Active Directory domain?

that makes no difference what so ever.  netbios is NOT a routable protocol, and even if it was, you would still run into the issue where there would be thousands of 'server's on the internet if  you were trying to access \\server\share\

your question has been answered..... many times the correct answer is simply 'no' which is the case with your question.  it is irrelevant that you dont like the answer, it is still correct.

as mentioned earlier,, the only way to do it is via a VPN or a point to point leased line,,,, but that really isn't over the internet though.

Ok...What if I make that UNC path as Web Share?

Oh great...but the problem is that it needs alot of configurations we cannot ask our customers to do technical issues like that.
What about make that UNC path as Web Sharing?

They host our application on that server and has their domain. What we are thinking that they can make that UNC path Web Sharing and then we can access that path www.theirdomain.com/ThePath...I think this is possible, isn't it?

if the server is a windows you can share the directory as web folder:
in the server: right click on the folder ->web sharing->share this folder
from the client es internet explorer: file->open...->write the url www.theirdomain.com/ThePath and check "open as web folder"

thats all folks :)

This is great...what about the security...is there any security risk?

if they are accessing it via www.theirdomain.com, then that is NOT a unc path but rather a DNS path,, which isn't what you asked for in your question.  The answer to your question has already been answered, and the answer is simply 'no' an i have explained why.

mikeleebrla you are wrong
you can access a UNC path from internet, this is possible (since 1987)!!
(Netbeui is not routable but if u have a windows a share and tcp/ip the world can see the share  )
Modifying lmhost you can use short name (without dot \\yourserver\share) or you can use the dns name (\\www.yourserver.com\share)
or  the ip (\\your-public-ip\share)

In 1987 was developed a method of encapsulating NetBIOS in a TCP packet (NBT) and released RFC 1001 - "Protocol Standard for a NetBIOS Service on a TCP/UDP Transport: Concepts and methods" and RFC 1002 - "Protocol standard for a NetBIOS service on a TCP/UDP transport: Detailed specifications".

the question is : Is it possible to access UNC path from Internet? if so what are the methods to do that?
the answer is: YES now as ten years ago.(correct setup, wins or lmhosts or direct ip  or dns ,firewall,user acl ... and so on)

Using your words:
It is irrelevant that you dont like the answer, it is still correct.

canali and others as I understand from your suggested method that we need to change lmhost file just on server, is that right? what else I need?
And do we need to make any change on client machines?

>That is provided that the NetBIOS ports are open, and *that* is a very bad idea.

I think this method is secured since the users will connect to their paths using their own Windows users accounts(Not Internet Guest account)

You need change lmhosts on the client, if u want connect \\serverName\servershare
123.123.123.123    serverName    #PRE    #DOM:domainOFtheServer
where 123.123.123.123 is the server ip
then from client Start->Run->\\serverName\servershare
probably(should) after a while a pop up windows ask you user an password for connect the share

for reference:
http://www.microsoft.com/technet/prodtechnol/winxppro/reskit/c24621675.mspx