When attempting to connect to a PC behind a remote desktop gateway you receive this message about the certificate being expired, press View Certificate
In the new window, select the "Details" tab.
Press "Copy to File"
The certificate export wizard will start, click Next.
Choose Next to accept the default selection.
The next step is where you choose the location and name for the temporary file that will contain the certificate. Click Browse.
I suggest selecting the Desktop from the option s in the left margin and entering a any file name that you will remember. Press Save.
A window confirming the location and name of the file is shown. Press Next.
Click Finish.
On your desktop, file the file that you just created and right click on it. Select Install Certificate.
This starts the import wizard. Choose Next to accept the default selection.
In the Certificate Store dialog, choose "Place the certificates in the following store" and choose Next
Select Trusted Root Certification Authorities and press OK
Press Next.
Press Finish to complete the certificate import Wizard.
You should see the confirmation dialogue.Â
Attempt your Remote Desktop Connection again.