Change SQL Server 2005 from Standard Edition to Workgroup

I have been tasked with performing an edition change from SQL Server 2005 Standard Edition to SQL Server 2005 Workgroup Edition, on Windows Server 2003 Standard Edition. Due to a previous failed attempt, I have a few questions:

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I have backed up my databases using the Backup tool in tasks when right clicking on a database in the server. Is this the correct approach? Or is there something I am possibly missing?

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I keep getting a warning when the installation wizard checks my system, that in order to do the edition change (I can't remember the feature of every edition of SQL Server 2005 so I'm not sure if we’re downgrading or upgrading!), I need to supply the SKUUPGRADE=1 parameter in command prompt. I type that statement (SKUUPGRADE=1) in sqlcmd. I'm assuming this is wrong. Please tell me how to fix this problem, if you know.

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After that, I select the default instance then the next step in the wizard tells me there is nothing to upgrade. I can't remember the exact error, but does this mean I need to uninstall my current version of SQL Server first?

Standard to Workgroup is a downgrade

This is the BOL page on upgrades

Unfortunately, you'll have to uninstall and reinstall. On the bright side, the master, msdb etc will simply restore into the "lower" version as long the version number is the same.

StackExchange Database Administrators Q#11165, answer score: 5