If you have already installed a VS2005 on the computer, you might still have configuration files that are now invalid.

Try the following steps:

• Delete the following directory:
  \Documents and Settings\<localuser>\Local Settings\Application
  Data\Microsoft\CoreCon and start the installation (highly recommended to backup before deleting)

• Look for the CLSID {1D273EC2-2A24-46fe-9F70-544B27811DF3} under
  HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\DeviceSDKInstaller\1.0

Look for DeviceSDKInstComp.dll(located at %ProgramFiles%\Microsoft Visual Studio
9.0\vc\vcpackages and try registering the DLL DeviceSDKInstComp.dll
Also look for the DLL DeviceSDKInstShim.dll   (Run regsvr32 "%Program Files%\Microsoft Visual Studio 9.0\VC\vcpackages\DeviceSDKInstComp.dll" to register)