Unable to fix permissions I have a Mac Mini 2006 and I accidentally set one of the permissions to No Access and so now the OS X will not boot up. ⌘ Cmd+R and ⌘ Cmd+S will not work. All I can do is hold the Opt and choose what to boot to.

I also do not have a Recovery partition. I made a Snow Leopard USB and when I try to repair permissions and verify permissions it straight up fails, but if I repair the HD that works.

How can I repair my computer?
If you have access to other Mac, you can boot yours in target mode. Attach it to the other system. It should show up as an external drive on the other system. From there, you can either fix the permission, or reload your operating system.

If you don't have access to another computer, you may want to ask around for a USB drive that has a system installed. (Friends, family, Apple store, Ebay, etc).