Error "The page cannot be displayed because the HTTP version is not supported" encountered (4249849)

The below error message might appear in the any of the Password Manager sites:

The page cannot be displayed because the HTTP version is not supported

CAUSE 1

Missing local permissions.

CAUSE 2

If this error message appears when attempting to use the SMS or Phone Call Starling authentication options in Password Manager, Microsoft .NET may not be properly configured to utilize TLS 1.2.

CAUSE 3

If this error message appears when attempting to send a passcode to a user's configured mobilephone, the format of the users mobile number in Active Directory is incorrect.

CAUSE 4

If the error appears when clicking on the Domain connections within the PMAdmin site, then this is related to Defect ID 125661.

RESOLUTION 1

Ensure that the necessary permissions are set for the Password Manager Service Account

RESOLUTION 2

1. Create the following four registry keys on the Password Manager host(s):

2. Reboot the Password Manager hosts

RESOLUTION 3

Starling 2FA requires that phone numbers must use E.164 phone number formatting.