You need to provide a username and a password if you want to connect to a Windows server through VPN using PPTP. Does the provided username have any function?
Let's say you use the user name "John" to connect to the network using PPTP VPN. John doesn't have the rights to access the folder "B" on the network. Does that mean I too can't access the folder if I use John's username to connect (in the Windows VPN connection dialog)? Or is the username completely meaningless and just establishes a tunnel over VPN that has nothing to do with the ACLs in any way?