Use the following procedure to remove the trusted root key from a Configuration Manager 2007 client. Use this procedure before reassigning a client from one hierarchy to a different hierarchy. As an alternative, you can reinstall the client with the new trusted root key, for example, by using client push from the new site, or by specifying the SMSPublicRootKey property with CCMSetup.exe.
To remove the trusted root key
On the client computer, run CCMSetup RESETKEYINFORMATION = TRUE.