While building a new SharePoint 2016 Farm for a client, continually got the following error:
A Certificate validation operation took ##### milliseconds……

This error will because it cant access the internet to validate the certificate.
To resolve the above error, add an entry in the host file for 127.0.0.1 crl.microsoft.com. The host file can be found here:
C:\Windows\System32\drivers\etc

I use NotePad ++ to edit the file and save it. If the host file cannot be saved because it is locked by another user, save the new host file to the desktop and delete the host file in the folder. Copy the host file from the desktop. Make sure there are no file extensions in the file, eg. .txt.