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When Exchange Server setup fails using /FORESTPREP

Find out why /FORESTPREP can be helpful during an Exchange setup and installation and what types of errors you need to watch for when using it.

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The Exchange 2000/2003 setup program can accept the command-line switch, /FORESTPREP, which allows administrators to extend the schema of Active Directory to include Exchange Server classes and attributes -- without actually performing an Exchange 2000/2003 installation.

This allows the Active Directory portion of an Exchange setup to be done independently from the actual Exchange program installation. If AD and Exchange are managed by different people at your organization, and you don't want them to step on each other's toes, this is highly useful.

Unfortunately, Exchange setup with /FORESTPREP can sometimes fail inexplicably with an error like this:

Setup failed while installing sub-component Microsoft Exchange 
Organization-Level Container Object with error code 0xC1037AE6 
(Please consult the installation logs for a detailed description)
You may cancel the installation or try the failed step again

Attempts to retry the installation usually fail too. If the install does complete, many elements of Exchange still won't work correctly. When this happens, cancel the installation and roll back any changes before attempting anything again.

One reason setup fails with /FORESTPREP is because the TEMP or TMP directory variables (which can be seen through the SET command) have one or more spaces in them, and 8.3 file-name generation has been disabled on the NTFS system partition. The setup program uses the 8.3 version of the pathname to the TEMP directory to store temporary setup options, so if it can't find that path on the disk, it'll fail.

To work around this, set the TEMP and TMP system variables to point to a directory path that has no spaces on it (such as C:\TEMP or C:\TMP). Just remember to create the corresponding folder as well, or the install will still fail!

About the author: Serdar Yegulalp is editor of the Windows Power Users Newsletter.

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