Interface Limitation (EAC vs. PowerShell): The graphical Exchange Admin Center (EAC) frequently returns "invalid" errors even when a key is perfectly valid.
Run a monthly PowerShell script to verify licensing status across your Exchange org: exchange 2019 product key invalid
Set-ExchangeServer
With the introduction of Exchange Server Subscription Edition (SE), licensing moves toward an entitlement-based model. For those upgrading, Exchange 2019 keys can often be used for the SE RTM version to support smooth in-place transitions. Success: The server will prompt you to restart
Interface Limitation (EAC vs. PowerShell): The graphical Exchange Admin Center (EAC) frequently returns "invalid" errors even when a key is perfectly valid.
Run a monthly PowerShell script to verify licensing status across your Exchange org:
Set-ExchangeServer
With the introduction of Exchange Server Subscription Edition (SE), licensing moves toward an entitlement-based model. For those upgrading, Exchange 2019 keys can often be used for the SE RTM version to support smooth in-place transitions.