Nice to see my original posts are still up. I was hoping that in the ensuing time someone had found a solution. At least I can now see many other posting the same problems. :) Thought I was losing it for a while.
We have 100% proven that the problem (in our case) is from the ISP blocking port 445 (possibly others but 445 for SURE) with the reasoning that it prevents the spread of some Internet "worms". It also just happens to prevent people who work from home from being able to map to their network drives at work.
What I was hoping was that eventually someone would comer up with a solution for this short of having to load a server using a different OS from Windows. The SMB protocol is the one needing port 445 as far as I can tell. Not all ISP block port 445 and the laptops that use those ISP's have no problem. Unless they travel. Then it is "hit or miss" as to whether the ISP for the Hotel they stay at blocks it.
I have run multiple tests to prove that this was in FACT the problem. Even the particular ISP in question which is a very large national ISP company freely admits they do this supposedly to prevent the spread of an unnamed Internet Worm. It also happens to prevent Business use of their Internet by Home Subscribers at they cannot map to their Business Servers which also need port 445 to map.
I have used WebDAV successfully to get around this but at a huge loss of speed and performance. Cloud services all do essentially the same thing and all have pretty much the same loss of speed.
If anyone has come across a method of allowing a drive mapping to be rerouted to any other port, that is the only hope I have short of changing to an alternate OS for the Office Server and even then I cant be sure until I try if it would help. I read somewhere about the possibility of routing through a proxy but again, the problem would still be that the requests for mapping are expected on port 445 on the server and they will not get through even to the proxy since the originating ISP is the one blocking the port from the User's system.
Any help or suggestions would be greatly appreciated I have posted this question now for several years with no one yet providing a working solution. Hope burns Eternal though :)