Cannot install software updates from Apple.

[HobbitShado]

I've had my macbook for almost two years now, and this is the first time i've ever had a problem with downloading or installing anything, especially from Apple.
I click on the Apple symbol in the corner, click Software Update, it finds a few updates I need to download, I click Download, and it downloads and installs them all the way till the very end, then BAM! it says Installation Failed.
I've noticed "Installation Failed" always appears after 'writing files' appears in the little installation status bar, but I checked my permissions, i've repaired them with Disc Utility, and there's nothing wrong with it.
In case this was just a bug with Software Update, I downloaded the .dmg files from Apple's website, and tried to install them from there. Same result.

Can anyone tell me what's going on?

 

[Detrius]

Here's what's going on: The installation failed.



Your possibilities are hardware, software, and wetware, and any one of those could be causing your problem. (That is, test your RAM, test your hard drive, try reinstalling the OS, etc...)

 

[HobbitShado]

The first thing I tried was reinstalling SL, but the problem persisted.

(That is, test your RAM, test your hard drive, etc...)

What do you mean by this?

 

[unixperience]

you could try a permissions repair (in disk utility)......
but if you reinstalled SL and the problem is still present... I doubt it is just a permissions problem..... I would guess a hard drive problem, but if you were able to reinstall SL... the hdd must work pretty well

 

[HobbitShado]

I wish it were just a permissions problem, but I've tried verifying and repairing the permissions through disk utility several times now and it hasn't helped

 

[DewGuy1999]

Have you tried verifying the disc (not permissions) with Disk Utility?
I've never tried this, but can you run Software Update when booted into Safe mode? To boot into Safe mode hold down the shift key while booting.

 

[HobbitShado]

Have you tried verifying the disc (not permissions) with Disk Utility?
I've never tried this, but can you run Software Update when booted into Safe mode? To boot into Safe mode hold down the shift key while booting.

I tried that today, and still no luck