In this scenario, the uninstall process is not completed successfully. Additionally, you receive the following error message:
The following error was generated when "$error.Clear(); uninstall-MsiPackage -PackagePath ($RoleInstallPath + "Mailbox\MSFTE.MSI") -Log
File ($RoleSetupLoggingPath + "\InstallSearch.msilog")" was run: "Couldn't open package 'C: \Program Files\Microsoft\Exchange Server\V14\Mail
box\MSFTE.MSI'. Another version of this product is already installed. Installation of this version cannot continue. To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel. Error code is 1638.".
The Exchange Server setup operation did not complete. Visit http://support.microsoft.com
and enter the Error ID to find more information.
Exchange Server setup encountered an error.