Older Remote Desktop Clients Can't Connect - Requires Network Level Authentication Error

I noticed this morning that my older thin client terminals started getting errors connecting to our central remote desktop session hosts.

It appears update KB 3075220 - part of KB 3080348 - just rolled through my session hosts over night and turned on the Network Level Authentication requirement.

I disabled the requirement by unchecking the "Allow connections only from computers running desktop with network level authentication" and it appears I'm back in business. Thanks for the early morning fire drill Microsoft.

https://support.microsoft.com/en-us/kb/3080348
MS15-082: Vulnerabilities in RDP could allow remote code execution: August 11, 2015

https://technet.microsoft.com/library/security/MS15-082
Vulnerabilities in RDP Could Allow Remote Code Execution (3080348)

After KB 3080348 update loaded, the "Network Level Authentication" was checked

Unchecked the "Network Level Authentication" requirement