When I run aspnet_regiis.exe, it just shows me the command line options and doesn't do anything - why?

I'm trying to run aspnet_regiis.exe in order to perform a couple of tasks on my development machine (running IIS 6 on Windows Server 2003 and a member of an Active Directory domain). So I change to the folder C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727, and run:

aspnet_regiis –i

But all that happens is that it displays the command line options for the utility, and doesn't actually execute or do anything. This doesn't work either:

aspnet_regiis –ga MYDOMAIN\user

In fact, any switch I try has the same effect - no actual action, just the display of the options.

Can anyone tell me why this might be?

First, check the start of the options listing, there might be an error there, here (Win7) with .NET 2's aspnet_regiis in an elevated PowerShell prompt I get:

Note: This utility has limited capabilities on the Windows Vista operating system. It is recommended that you use the "Turn on or off Windows features" option of the "Programs" component of Control Panel to install or remove ASP.NET. It is also recommended that you use the IIS Manager component or the Appcmd.exe tool to configure ASP.NET applications.

And then a listing of the options.

Second try:

aspnet_regiis -lk

to just list the mappings that exist this might:

• fail like above: so use IIS manager to install/configure on IIS7 or 7.5.
• list nothing, or give an error: ensure ASP.NET is installed (newer OS's do not enable it by default)
• something else...

In my experience on 2008R2, you have to cd to the directory it lives in

    C:\Windows\Microsoft.NET\Framework\v4.0.30319

then run the command with options from there. Otherwise, it will do nothing but spit out options.

    aspnet_regiis –i