Debugging OpenVPN Connection Issues: Route Addition Failures and Access Denied Errors


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After analyzing your OpenVPN client logs, the primary error manifests when attempting to add routes:

ROUTE: route addition failed using CreateIpForwardEntry: Access is denied. [status=5 if_index=11]
The requested operation requires elevation.

The log reveals a critical Windows permission issue during the routing phase. While the TLS handshake completes successfully (as shown by the VERIFY OK messages), the subsequent route operations fail due to:

  • Insufficient administrative privileges
  • Potential UAC restrictions
  • TAP adapter permission conflicts

Solution 1: Run as Administrator
Right-click your OpenVPN GUI shortcut and select "Run as administrator". For CLI users:

runas /user:Administrator "openvpn --config client.ovpn"

Solution 2: Permanent Privilege Assignment
Create a scheduled task with highest privileges:

$action = New-ScheduledTaskAction -Execute 'C:\Program Files\OpenVPN\bin\openvpn.exe' -Argument '--config "C:\Path\to\config.ovpn"'
$trigger = New-ScheduledTaskTrigger -AtLogOn
$principal = New-ScheduledTaskPrincipal -UserId "$env:USERDOMAIN\$env:USERNAME" -RunLevel Highest
Register-ScheduledTask -TaskName "OpenVPN AutoConnect" -Action $action -Trigger $trigger -Principal $principal

Modify your client.ovpn to include route-nopull if you want manual route control:

route-nopull
route 0.0.0.0 128.0.0.0 vpn_gateway
route 128.0.0.0 128.0.0.0 vpn_gateway

After connection, verify routing with:

route print
tracert 8.8.8.8
ipconfig /all

When running with elevated privileges:

  • Ensure your OpenVPN config files are in secure locations
  • Verify server certificate fingerprints
  • Consider using --management option for better control

If issues persist, reset network components:

netsh winsock reset
netsh int ip reset
ipconfig /flushdns

After examining your OpenVPN connection logs, I can see the core issue revolves around route addition failures with "Access is denied" errors. The VPN establishes the initial connection successfully but fails when attempting to modify routing tables:

Tue Nov 01 19:25:36 2011 ROUTE: route addition failed using CreateIpForwardEntry: Access is denied. [status=5 if_index=11]
Tue Nov 01 19:25:36 2011 Route addition via IPAPI failed [adaptive]
The requested operation requires elevation.

The key symptoms indicate:

  • Successful TLS handshake and authentication
  • Proper TAP adapter initialization
  • Failure occurs during route modification phase
  • Multiple "Access is denied" (status=5) errors
  • Fallback to route.exe also fails due to lack of elevation

Here's how to resolve this properly:

1. Run OpenVPN as Administrator

Right-click your OpenVPN client shortcut and select "Run as administrator". Alternatively, configure it permanently:

# Create a scheduled task with highest privileges
$action = New-ScheduledTaskAction -Execute "C:\Program Files\OpenVPN\bin\openvpn-gui.exe"
$principal = New-ScheduledTaskPrincipal -UserId "$env:USERDOMAIN\$env:USERNAME" -RunLevel Highest
Register-ScheduledTask -Action $action -Principal $principal -TaskName "OpenVPN Elevated" -Description "Runs OpenVPN with admin rights"

2. Modify OpenVPN Configuration

Add these directives to your client configuration file (.ovpn):

# Disable route addition fallback
route-noexec
route-delay 0

# Manual route addition script
script-security 2
route-up "C:\\Program Files\\OpenVPN\\config\\add_routes.bat"

3. Create Route Addition Script

Create add_routes.bat with the following content:

@echo off
:: Requires admin privileges
:: Add routes manually after VPN connection
route add 208.111.39.186 mask 255.255.255.255 192.168.11.1
route add 0.0.0.0 mask 128.0.0.0 10.8.0.9
route add 128.0.0.0 mask 128.0.0.0 10.8.0.9
route add 10.8.0.1 mask 255.255.255.255 10.8.0.9

After implementing these changes:

  1. Check routing table with route print
  2. Verify VPN IP with ipconfig /all
  3. Test connectivity to VPN subnet: ping 10.8.0.1
  4. Confirm traffic routing: tracert 8.8.8.8

For enterprise environments, consider these advanced options:

# Group Policy solution
1. Open gpedit.msc
2. Navigate to: Computer Configuration → Windows Settings → Security Settings → Local Policies → User Rights Assignment
3. Add your user to "Create symbolic links" and "Debug programs"
4. Apply and reboot