When you face a strange VPN connectivity problems, try to check the error message and if it is “Error 619: A Connection to the remote computer could not be established, so the port used for this connection was closed.” then you have a chance to resolve it.
To resolve that issue:
1. Make sure your Router Supports PPTP Passthrough.
2. Make Sure TCP Port 1723 and 47 protocol (GRE) are Open.
3. Make sure you Allow Connection/Trusted Connection under Your Firewall Application. or Try to Disable Firewall and Re-connect.
If still you are unable to resolve the issue. It means PPTP is blocked by your ISP. So you will require to use L2TP.
If you require any assistance , please submit ticket from Client Area or email firstname.lastname@example.org.