The setup procedure described in the SDK documentation to reinstall Indigo has some bad file references. The docs should be updated for beta1 but until then this is the correct procedure (with the correct file paths):

"%windir%\microsoft.net\framework\v2.0.50215\aspnet_regiis.exe" –i
"%windir%\microsoft.net\framework\v2.0.50215\xws_reg.exe" -i
cscript "%windir%\microsoft.net\framework\v2.0.50215\InstallIndigo.js"