Error 1928. error registering COM+ application. Contact your support personnel for more information.
orError 5003. Regsvcs failed for assembly c:\program files\Microsoft Biztalk Server 2004\Microsoft.Biztalk.Deployment.dll. Return code 1. (BizTalk SP1)
I ran into the above error while installing BizTalk 2004 dev/sdk components onto my windows xp/sp2 box and spent a few hours debugging the problem and managed to find a workaround. The problem stems from overly tight default permissions on keys created under HKLM\software\classes during the install.