[Cross-Posted on StackOverflow.com as well because the question relates to development. Feel free to let me know where it best belongs.]

Hi all,

I'll try to bullet-point to keep it short:

Background / Issue

• Trying to install ASP.NET MVC 3 RC on my Windows 7 machine.
• Uninstalled other versions of MVC (2 and 3 Beta 1).
• Ran the installer -- got a generic error, 2203.
• Log files said that it was a permissions error on C:\Windows\Installer.
• Checked C:\Windows\Installer -- sure enough, it's marked as read-only.
• I un-checked "Read-Only" in the folder properties and applied. It appears to open the dialog and apply to all files.
• However, when clicking properties again, the read-only box is backed to checked.
• Checked the security tab of the folder -- both system and the Administrators group have full access.
• I checked ownership -- the Administrators group is listed as an owner.
• Verified that I'm in the system as an Administrator (in fact, the only account in the Administrators group besides Administrator).

So, what gives? Thanks in advance for any help you can provide!