OS X won't start up, permissions won't repair

[Yixian]

After a few messy shut downs, OS X won't start up, it hangs at my wallpaper with no desktop. I tried repairing permissions but "a valid package cannot be found", I tried repairing disk, didn't work, I tried defragging disk, didn't work.

I popped in my OS X CD and tried to archive and install, but the option to preserve users and settings (so I take it all my music etc.) is greyed out... why the hell?

Somebody save me

 

[mkrishnan]

Okay, slow down a sec. In order to repair the disk, you must repair from the install DVD (or from single user mode). So go back into the DVD, and instead of following the install prompts, from the menus, run Disk Utility. Use it to repair the disk. DO NOT use it to repair permissions.

If it does work for repairing the disk, try booting off it, see if you can get into OS X, and then try repairing permissions.

 

[Machead III]

Neither repairing the disk from the boot disc, nor fsck from Single User Mode worked. Booting into target disk mode revealed basesystem.pkg to be missing, explaining why I couldn't repair permissions. Replaced this, repaired permissions, still no dice.

I'm archiving and installing, but it won't let me preserve users etc/ - can I migrate from the archived folder to get all my users and settings back?

 

[disconap]

Yes. Before archive/install existed, that was how we all did it.

Just back up your user folder, reinstall OSX, create an identically named user (note: with the same password you currently use), and then replace the user folder with the backup. As I recall, there may be a couple other little things you have to do once or twice (like rebooting and running a permissions repair stuff like that), but otherwise it's that easy.