Grand IIS7 metabase on Windows 7

I have this instruction to Grand IIS metabase aspnet_regiis.exe -i aspnet_regiis -ga ASPNET

in Window Xp IIS6 can run then in Windows 7 for this error

C:\Windows\Microsoft.NET\Framework\v2.0.50727>%windir%\Microsoft.NET\Framework\v 2.0.50727\aspnet_regiis -ga ASPNET Start granting ASPNET access to the IIS metabase and other directories used by ASP.NET. An error has occurred: 0x8007089a The specified username is invalid.