The local computer is already running Exchange Server_ExchangeAlreadyInstalled
Applies to: Exchange Server
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Microsoft® Exchange Server 2007 setup cannot continue because the local computer has previous Microsoft Exchange components installed.
Exchange 2007 setup requires that the local computer not have existing Microsoft Exchange components installed.
To resolve this issue, remove any Microsoft Exchange 2000 Server or Microsoft Exchange Server 2003 components, and then rerun Microsoft Exchange setup.To remove Microsoft Exchange components
Click Start, point to Settings, and then click Control Panel.
Double-click Add or Remove Programs.
In the Currently installed programs list, click Microsoft Exchange, and then click Change/Remove.
In Microsoft Exchange Installation Wizard, click Next.
In the Action list on the Component Selection page, click the down arrow next to each component that has been installed, and then click Remove.
Note: Installed components have a check mark in the Action list. When you click Remove, the check mark is replaced by the word Remove.
Click Next two times.