Azure AD sync has been running for over a year now but recently it failed. We are now getting an error message when we run Azure AD connect. the error message is "Unable to install the Synchronization Service."
I've tried making the admin account a local account and running the application again but still, I get the same error. I've also renamed the "Microsoft Azure folder" in program files but still, I get the error message. I've also tried running AD connect in a different DC. I've uninstalled and reinstalled the application.
Anyone with any suggestion on how to solve this issue?