Quick Fix: New-FederationTrust 426 Upgrade Required

I am working on an Exchange migration project currently, and setting up some things in a lab. As part of that I am converting what was a Modern Hybrid setup with the Hybrid Agent, to a Classic Hybrid, using connectors and what not.

I was trying to use New-FederationTrust setup a Federation trust and received the following:

Unable to access the Federation Metadata document from the federation partner. Detailed information “The remote server returned an error: (426) Upgrade Required.”

Immediately thought I should enable TLS 1.2 in the PowerShell Session, however this did not help.

I realised that as this is an almost new lab server chances are I hadn’t gone through and properly enabled TLS 1.2 in .Net. I loaded up my previous article on that and looked for the quick registry entries I needed to create.

New-ItemProperty "HKLM:\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v2.0.50727" -Name DefaultSecureProtocols -Type DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Microsoft\.NETFramework\v2.0.50727" -Name DefaultSecureProtocols -Type DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319" -Name DefaultSecureProtocols -Type DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Microsoft\.NETFramework\v4.0.30319" -Name DefaultSecureProtocols -Type DWORD -Value 1

However, this also did not solve it.

The solution was that I also needed to add two additional registry entries, which are documented here.

New-ItemProperty "HKLM:\SOFTWARE\Microsoft\.NETFramework\v2.0.50727" -Name SystemDefaultTlsVersions -PropertyType DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Microsoft\Wow6432Node\.NETFramework\v2.0.50727" -Name SystemDefaultTlsVersions -PropertyType DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Microsoft\.NETFramework\v4.0.30319" -Name SystemDefaultTlsVersions -PropertyType DWORD -Value 1
New-ItemProperty "HKLM:\SOFTWARE\Microsoft\Wow6432Node\.NETFramework\v4.0.30319" -Name SystemDefaultTlsVersions -PropertyType DWORD -Value 1

After rebooting, I was able to create the Federation Trust successfully.