A solution to Mac OS X (10.8.3) App Store Update Error

N.B. This is a possible solution for those experiencing similar issues, not a request for assistance.

Hi there,

I recently bought my first mac and having been a windows user for years, I naturally felt unsafe browsing without any anti-virus software. So, enter Avast...

I've been using Avast for a while now, without any problems. The Mac continued functioning normally to my knowledge. Then I noticed yesterday that App Store, while it could show me all the apps and allow me to download and install new apps, suddenly couldn't update the existing ones or the system software. I just kept getting the following App Store error:

NSURLErrorDomain -1012

I hunted for a solution and couldn't find it. Until I had the idea to paste Apple's https server URL into Safari, as referenced in Console at "/var/log/install.log" under "Files" relating to this error. There, I discovered a clue that Avast was behind this problem. In my case, the console detailed an accompanying error of:

Failed Software Update - trust evaluation failed in SecTrustEvaluate with result: 5

After figuring out that Avast was probably behind this error, I went into the application preferences for Avast and tweaked until I could turn the error on and off. Basically, the error appears to be a certificate mismatch issue between the certificate's registered URL and the URL the App Store is trying to connect to.

In Avast preferences, you want to click on "Advanced..." of the Web Shield. There you can add an https ignore rule for the server that App Store is trying to connect to (https://swscan.apple.com in my case).

Obviously, you will only want to do this if you trust the server that the App Store is trying to connect to! If in doubt, leave it out. It's quite possible that it is an issue that will eventually resolve itself once either of the organisations involved update the certificates accordingly.

I felt compelled to write up my findings, since finding anything about these errors proved difficult initially and none of the suggested fixes that I did find, worked for me. Hopefully, this will work for you... this time!

Good luck.

A Mac Newbie