Exchange Server 2019 Cumulative Update 14 (CU14) or newer. Always download the latest CU, not the RTM version.

C:\Exchange2019\Setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms C:\Exchange2019\Setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms C:\Exchange2019\Setup.exe /PrepareAllDomains /IAcceptExchangeServerLicenseTerms

Standard support for Microsoft Exchange Server 2019 has concluded. Organizations without an active Extended Security Update (ESU) contract are highly encouraged by Microsoft to migrate to the Exchange Server Subscription Edition (SE) . 🛠️ Key Deployment Steps

The initial ISO you download is likely the version or an early Cumulative Update (CU). Exchange 2019 follows a CU release cadence (approximately every 6 months).