I have users connecting from Windows laptops (Win 7 thru Win 10) to the office network using the built-in Microsoft VPN client and standard PPTP connection.
I believe I have all the necessary ports and protocols allowed through the firewall which is a SonicWALL NSA2400.
Then I have Routing and Remote Access set up on a server running Windows Server 2012 Standard.
The VPN works fine for some users. And when I test it, it seems to work fine. But a few users have a weird issue where the VPN will connect normally and they are able to access network resources normally at first and then stops working.
Typically, the user will connect, access a server (\\servername), and begin to browse shared folders. It will work perfectly for maybe the first 3-5 folders they click on but then it will suddenly stop working. Explorer will show the green bar slowly filling the address bar but then nothing else will come up. The VPN connection will still be active and connected and I can still ping servers and do DNS lookups. But shares can no longer be accessed.
Disconnecting the reconnecting the VPN will start the process over where it works for a bit and then stops.
Any ideas what might be happening?