SQL Server 2005 Express on Vista

I've hit yesterday some problems when installing SQL Server 2005 Express on my Vista machine, so I though I'd share some of my findings that can help you avoid spending time searching for an answer.

First of all, you need SP2 of SQL Server 2005 Express on Vista (the RTM installs, but warns you about compatibility issues). There are three different packages available right now:

• SQL Server 2005 Express Edition SP2 (then you can install separately SQL Server Management Studio Express)
• SQL Server 2005 Express Edition with Advanced  Services SP2 (includes SQL Server Management Studio Express, Reporting Services  and Full-Text Search)
• SQL Server 2005 Express Edition Toolkit (brings Connectivity Components, Business Intelligence Development Studio, and a Software Development Kit)

There is a good link on MSDN (here) where you can learn more about these packages.

Here comes the tricky part. On Vista, you might encounter a strange error during setup stating "SQL Server Setup Failed to compile the Managed Object Format (MOF) file ...". If this happens, don't cancel the setup process! The problem appears as a result of a WMI repository problem and can be fixed easily by opening a command prompt with elevated privileges (Run as administrator) and running two times the "winmgmt /salvagerepository" command (the first time you get a failure message, but the second time it lets you know that the WMI repository was successfully salvaged). Once this is done, you can safely resume the setup.