Purpose:

The reason this is important is that some people are convinced that they have to uninstall SharePoint or even completely rebuild their box in order to start from scratch.  This is not so.

NOTE:: 

• This assumes you’ve backed up and kept everything you want to keep.
• The psconfig.exe command is located in the “%WINDIR%\Program Files\Common Files\Microsoft Shared\web server extensions\12\bin” folder.
• this does not remove any custom code or other types of files from the 12 hive
• this procedure will keep the SharePoint patch and service pack level of the host so there’s no need to rerun hotfixes or anything

Procedure:

1. From the host that runs Central Admionistration, run this command psconfig.exe -cmd configdb -disconnect to disconnect Central Admin from your database.
2. Run this command: psconfig.exe -cmd adminvs -unprovision to unprovision the Central Administration site.
3. Delete all application pools and web sites from affected IIS servers.
4. Delete any SQL user databases related to SharePoint e.g. SharedServices*,SharePoint_AdminContent*,SharePoint_Config,WSS_Search

Now you’re ready to run the Configuration Wizard just as if you had never set up a farm.

TechNet info on psconfig.exe

“I say we take off and nuke the site from orbit…  It’s the only way to be sure.“

  – Aliens