Notes from the lab: Migrating Azure AD Connect and then we cannot sync

This is a quick blog post regarding my own Azure AD Connect migration and a nasty error after trying to connect again for an initial connection and synchronisation.

A little insight in my environment, I already had the latest version running of Azure AD Connect namely on my Windows Server 2019. See Azure AD Connect: Version release history – Microsoft Entra | Microsoft Docs

So, I spun up a new Windows Server 2022 and installed the Azure AD Connect role on it, imported my configuration file like described here How to import and export Azure AD Connect configuration settings – Microsoft Entra | Microsoft Docs

And then I got below error when trying to configure my new server:

The error put me onto the blog of Azure AD Connect – Unable to validate credentials due to an unexpected error. – but the issue mentioned wasn’t my issue, my GA account doesn’t have any expiry set and the logon was working everywhere else. The point to note is that I have only modern authentication enabled and MFA with number matching enabled in my tenant. So afterwards running the installation in context with /InteractiveAuth did resolve the issue. Afterwards closing, rebooting etc. never gave the error again and al logins are still providing the popup of modern and MFA prompt.

Strange thing is that I’ve had this enabled for a very long time now. Seems that in the latest versions perhaps there are some changes regarding the modern auth popup.

Hope it helps!