If your Okta Tenant (Org) is already migrated to TLS 1.2 (ahead of the August 2018 deadline), these changes may be required in your environment to facilitate MFA for RDP and/or ADFS.
TLS 1.2 is supported on .NET 4.6 and above. Here is how to determine whether .NET 4.6 is installed on your system:
If .NET 4.6 is not installed, click the following link to install it: https://www.microsoft.com/en-us/download/details.aspx?id=53344
Enabling TLS 1.2 on .NET
Add "SchUseStrongCrypto" registry DWORD under .NET 4.0 registry option (as mentioned here: http://www.processio.com/enable-outbound-tls-1-1-1-2-windows-server/)Registry change Illustrated.
Note: the ADFS Service must be restarted after performing the above step.
Enabling TLS 1.2 on IE
Note: This section is only needed for RDP and EPCS (*not* ADFS)