Open Control Panel by typing control panel in the search bar
Open the Network and Sharing Center Click on <Change adapter settings>

Right click the name of your: VPN Connection LION, LION-VPN, Universiteit Leiden and select Properties

Click on the <Security tab>

Chance all options like above.

Left click one of the above icon.

Click on Connect on your VPN connection name.

Fill in your credentials when you have choose the Push option in DUO and click OK
For example, if you wanted to use a passcode to authenticate instead of Duo Push , you Should enter (don’t forget the comma after your password):

username: bob
password: *******,123456

If you wanted to use a Yubikey to authenticate instead of Duo Push , you should enter (don’t forget the comma after your password):

username: bob
password: *******,hold your finger on the yubikey