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Fixing VPN connection issues

If you cannot successfully ping from both sides of the VPN connection, then use the following tips.

  1. Ensure that UDP port 1194 (OpenVPN) is open on the corporate and any host-based source server firewalls (Windows Firewall), and configure the firewalls to allow communication.
  2. On the repository server, run ipconfig /all and check that the TAP adapter has been assigned IP address 10.8.0.1.
  1. If you DO NOT see an address, then restart the OpenVPN service using the Windows services applet.
  2. If you still DO NOT see an address, check the OpenVPN server log files, then contact Double-Take Software technical support.
  1. On the source server, run ipconfig /all and check that the TAP adapter has been assigned an IP address in the 10.8.0.0/24 range.
  1. If you do not see an address,
  1. Check the OpenVPN client and server log files for errors.
  1. Restart the OpenVPN service using the Windows services applet.
  1. If the IP address is NOT in the 10.8.0.0/24 range:
  1. Run: ipconfig /renew "Local Area Connection 2"

where “Local Area Connection 2” is the name of the OpenVPN TAP (or Tap-Win32) adapter

  1. If you still see no address or the address is not in the 10.8.0.0/24 range, check the OpenVPN client and server log files.
  1. If the IP address is in the range defined and you cannot ping, then try the following.
  1. Check the registry setting for “HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Tcpip\Parameters\
    DisableDhcpMediaSense”     has value: “1” - change it to “0”
WARNING: Editing the registry incorrectly can cause problems with the operating system; therefore, it is recommended that you use caution when removing registry keys and values. You may want to save or export your registry keys to another file so that you can restore your registry if needed.
Note: For more information on this registry setting, see Microsoft KnowledgeBase article 239924.
  1. Stop and start the OpenVPN Service
  2. If you still cannot ping, check the OpenVPN client and server log files, then contact Double-Take Software technical support.