There’s lot of information out there on how to get Cisco VPN to connect to your work computer using Windows 10, but only one site I’ve found actually gives information that works:

5 Steps to make Cisco VPN work in Windows 10

I’ve summed this up below as it contains too much information, this is what worked for me, I was getting:

“Error 433 Secure VPN Connection terminated locally by the Client. Reason 433: Reason not specified by peer.”

The likely reason is due to the DNE LightWeight Filter network client not being properly installed by the Cisco Systems VPN installer.

To solve this, please try to do the following

A) First, uninstall any Cisco VPN Client software you may have installed earlier
B) Reboot your computer.
C) Run winfix.exe, to ensure the DNE is properly cleaned up, as no doubt this isn’t your first attempt.
D) Reboot your computer again.
E) Download Sonic VPN software from here: 32-bit or 64-bit
F) Install the Sonic VPN software from above.
G) Reboot your computer.
H) Reinstall the Cisco VPN Client software again. (If you face a version not suitable for Windows 10 issue, run the msi file instead of the exe file)
I) Install the Cisco VPN Client Software: 32-bit Windows VPN Client (version 5.0.07) or 64-bit Windows VPN Client (version 5.0.07)
J)Reboot.
K)Make changes to the registry:
Open Registry editor regedit in Run prompt

Browse to the Registry Key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CVirtA

Select the Display Name to modify, and remove the leading characters from the value data value as shown below,

For x86 machine, shorten the string “@oem8.inf,%CVirtA_Desc%;Cisco Systems VPN Adapter” to just “Cisco Systems VPN Adapter”

Or for x64 machine, shorten the string”@oem8.inf,%CVirtA_Desc%;Cisco Systems VPN Adapter for 64-bit Windows” to just “Cisco Systems VPN Adapter for 64-bit Windows”
L) Reboot your computer.
M) Your Cisco VPN Client should now work in Windows 10

Are you getting a 412 error?

I was getting this when I was trying to connect from within my organisation, this isn’t allowed as your organisation is blocking the required UDP ports 4500/500

Solution, try connecting from somewhere external to your organisation.

If this doesn’t work for you then you’ll have to delve into the full site to work it out for your set-up.

Windows 10 Update Uninstalls “Cisco Systems VPN Adapter”

I noticed that a recent Windows 10 update kindly uninstalled my Cisco VPN Adapter! Why? I’m not sure. Apparently ‘removed due to incompatibility issues’ But if you want it back, you’ll need to uninstall ‘Cisco Systems VPN Client 5.0.07.0440‘ in Add or Remove programs then re-run the msi installer, this will FAIL, now jump to the unzipped directory ‘C:\Users\\AppData\Local\Temp‘ to find ‘vpnclient_setup.msi‘, run this, you might need to run it twice as it complains about failing to add itself to the Services. Then you need to re-edit the ‘Display Name‘ using the Registry key in Regedit, as above.