This article was previously published under Q170280
Retired KB Content Disclaimer
This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
To upgrade the Standard Edition of Microsoft Exchange Server to theEnterprise Edition of Microsoft Exchange Server, run the Setup program fromthe Exchange Server Enterprise Edition compact disc and click the Reinstall button.
To install any additional components or connectors included in theEnterprise Edition of Exchange Server, run the setup program again andclick Add/Remove.
Note Any Exchange service packs or hotfixes must be reapplied after you upgrade. Once upgraded, you cannot downgrade Exchange Enterprise Server edition to the standard version of Exchange Server.
For more information about a case in which the upgrade is not possible because of the different packaging of the product, click the following article number to view the article in the Microsoft Knowledge Base:
312426 No option to upgrade from Exchange 2000 Server Standard Edition to Exchange 2000 Enterprise Server