IIS won't install on Windows Server 2003

Symptoms:

• Error message after failed install: "iis could not be installed on this server"
• The configure your server.log is:

Configurations for an Application Server
IIS could not be installed on this server.
To install IIS, try running the Configure Your Server Wizard again, or use Add or Remove Programs.

• When checking the iis6.log in the Windows directory this error appears:

OC_COMPLETE_INSTALLATION:iis_core:MyMessageBox: Title:IIS Setup Error, Msg:CoGetClassObject
0x80040154=Class not registered

• When trying to connect to a server in the IIS Management Console, an error message saying that IIS needs to be version 4.0 or greater

Solution:

• Uninstall all versions of .net framework and service packs
• Uninstall IIS through Add/Remove Programs
• Reinstall IIS
• Reinstall .net frameworks as needed

It looks like this is a .net error and removing the framework removes the error, then IIS can successfully install.