I'm using the AnyConnect client to login to our VPN. AnyConnect 3.1.00495 is running on Windows 7 home premium. Before Christmas, it was working fine. I've not made any changes to hardware or the home network. How do I remedy the error Unable to modify the IP forwarding table?
The VPN client was unable to modify the IP forwarding table. A VPN connection will not be established. Please restart your computer or device, then try again.
Description AnyConnect failed to apply all the VPN configuration settings to the endpoint IP forwarding table. A VPN connection is not permitted because this failure could compromise both its security and operation. This error is unrecoverable.
Recommended User Response Restart your computer or device, then try a new VPN connection. If the problem persists, run DART. (See Using DART to Gather Troubleshooting Information.) Report the error to your organization's technical support and include the DART bundle.
Recommended Administrator Response Open a case with the Cisco Technical Assistance Center (TAC) and include the DART bundle.
found it here
I would also recommend checking to make sure the client is not receiving the same IP address from the Cisco appliance that they have received from the network that is local to them.
local workstations ip address is 192.168.1.10
and the vpn is trying to assign the client 192.168.1.10
thus creating a conflict. Many different ways of resolving this problem, first obvious one would be fix your firewall so it does not pass out such a common home networked ip address.
Applies at least to MacOS: You should also check, that VPN does not give same DNS server IP that you have manually entered via Network settings for your adapter. Same error occurs also in that case.
I encountered this issue today and resolved very quickly with the help of IT support.
Cisco Anyconnect VPN fails to establish VPN connection and troughs error "The VPN client was unable to modify the IP forwarding table. A VPN connection will not be established. Please restart your computer or device, then try again."
Delete the following files and restart the PC(This is for windows 10 laptop).
C:\ProgramData\Cisco\Cisco AnyConnect Secure Mobility Client\routechangesv4.bin
C:\ProgramData\Cisco\Cisco AnyConnect Secure Mobility Client\routechangesv6.bin
Worked for me, thanks!
You will need to run as administrator to del the files.
To do so - Search for “cmd”, then right click on “Command Prompt” and select “Run as Administrator”.