When attempting to use the SMS or Phone Call Starling authentication options in Password Manager, the following error is observed:
The page cannot be displayed because the HTTP version is not supported
Reviewing the corresponding Event Viewer logs displays the following error:
Could not create SSL/TLS secure channel
Verify Cumulative Hotfix 319839 is installed and hosts have been rebooted.
Configure .NET for strong cryptography as noted in the following Microsoft KB article (under Configure for strong cryptography section):