“A connection between your computer and the VPN server has been established but the VPN connection cannot be completed.”
Error Code 806 – TThe most common cause of this failure is that at least one Internet device (such as a firewall or router) between your computer and the VPN server is not configured to allow GRE protocol packets (Generic Routing Encapsulation). If the problem persists, contact your network administrator or Internet service provider.
This error indicates that a router firewall prevents any VPN protocol traffic between the client and the server. Most often, it is the TCP port 1723 that is involved and must be opened by the appropriate network administrator.
If your VPN uses PPTP, you can try the following steps as you read. Point-to-Point Tunneling Protocol (PPTP) is a method of implementing virtual private networks (VPNs). PPTP uses a control channel over TCP and a GRE tunnel to encapsulate PPP packets. PPTP is considered cryptographically broken and its use is no longer recommended by Microsoft.
Method 1. Access the TCP Port 1723 and open it.
Now, in order to solve the blocked VPN virtual private network blocking problem, you need to determine exactly what the VPN blocking is. That said, you need to know that a firewall or router probably needs to be configured first for GRE. See the steps below to open TCP port 1723 in Windows 10:
Step 1: Click on the Cortana button and open the app’s search box.
Step 2: Type in ‘firewall’ and hit Enter. In the list, select and open Windows Defender Firewall.
Step 3: Select Inbound Rules on the left side of the window.
Step 4: In the Steps, select Action>New Rule option.
Step 5: Open the Port box and type in 1723 in the Specific local ports text box.
Step 6: Click Next and select Allow the connection.
Step 7: In the Next window, make sure that all the rules apply and all the checkboxes are checked.
Step 8: Select the Finish button to save all the changes and apply them. Your VPN should work now.
Method 2. You can also disable the antivirus software on your computer, as well as the Windows Firewall, to resolve the problem that is blocked by the GRE GRE network.
Some settings and configurations may prevent the VPN from connecting correctly, resulting in errors. Although we do not recommend trying this fix, it might be a viable option if all else fails. Be sure to back up all important information on your computer or (preferably) on an external drive. We also recommend that you enable these services after resolving your VPN problem and an anti-malware program.
Method 3. Open Protocol 47 (GRE).
Since the extended error note indicates that you need to configure the GRE protocol, this is probably what you need to do. Follow these simple instructions to open the protocol.
Step 1: Open Windows Defender Firewall and Advanced Security Window
Step 2: Right-click Inbound Rules and select the New Rule option.
Step 3: Choose the Custom option and click Protocol and Ports on the left of the window.
Step 4: Find GRE from the drop-down menu and click the Name.
Step 5: Hit Finish to close the wizard’s window. You have configured the GRE protocol: the error should not be an issue anymore.
Method 4. Check if your router’s PPTP setting is switched on.
To do this, you need to know the type of your router and configure it accordingly. Error 806 may appear when new protocols are used for VPNs and, as you use other methods of configuring your VPN, make sure that you will need to adjust the settings in your router software in order to establish a constraint. free connection.