So, I'm looking for an explanation.
Just today I loaded up 10.7.3 on my production Mac. There were no issues during the install. I was working just fine when I had some issue downloading a file and the error that I got led me to believe that either my system disk (Macintosh HD - M HD) was full or there was some permissions issue. It turned out that the message was really nothing, but I reacted to it as though it was something.
My first thing to do was to look at the permission on M HD; not sure why, but something led me there. I noticed and panicked that the only "user" with read and write was System;wheel and everyone was read only. I thought that this was obviously wrong, so I logged in as the admin and added my specific user in, but even then I was not able to change it to RW and then I set him as owner; still no go. Finally I removed him from the list and then my problems started. I was unable to access anything, even log in, with my ID. I ended up logging in as the admin and adding my user ID back in and then everything was OK.
I checked on another Mac that I have here and apparently the permissions that I saw when I looked at M HD were really OK... so I screwed myself up.
So, I guess I have some questions. One, is who is supposed to be the owner of M HD? Should I set that back ? Second, why did my user lose access to M HD when I removed him when the everyone group still had access? Can I fix it so that I can have access if my user ID isn't in the list. Was the fact that I made me owner the crux of the issues with my ID's access?