This morning I proceeded to do the 10.8.3 update on my iMac. Upon restarting I got the message that the update failed, no other information. This is the first time for me that this happens.
Returning to Software Update in the App Store app, it doesn't list the OS update anymore. I wish to retry, but how do I proceed? And are there logs I can look up for more specific information about this failure?
I see there are two updates.
OS X Mountain Lion Update v10.8.3 (Combo) And the delta version.
Which did you try and would the other solve your problem.
The answer by Barney 15E in the following link might also help.