HTTP 404 error in IIS 6 on new ASP.NET application install

If you're putting together an IIS 6 box and you're getting 404 errors on all your ASP.NET applications, do the following:

1. Open IIS Manager on the IIS box
2. Expand the computer_name node
3. Click on Web Service Extensions
4. Ensure the Status for ASP.NET v2.0.50727 is Allowed