Failed to verify preflight file ... App Store broken after Mavericks upgrade

What worked for me was changing the certificate preferences in Keychain Access (open Keychain Access app and then go to preferences).

I just changed both of the first two options to 'Best Attempt', they were originaly at 'Require if certificate indicates'.

Hope this Helps

Very helpful solution - it worked perfectly for me and now I can upgrade previously purchased apps including Pages and Numbers.

Thnx a bunch, worked for me too...

Thank you so much for the fix!

Be Patient, I kept getting the same message, I "Repaired disk permissions and safe startup" as recommended on Support Chat. Eventually received a message from iCloud stating: Updates are available to download. Everything went smoothly updating all my Apple App's and Upgrading Pixelmator to V3...

you should indicate that p1991atric answered your question, as this correction worked perfectly and immedicately.

How?

What worked for me was changing the certificate preferences in Keychain Access (open Keychain Access app and then go to preferences).

I just changed both of the first two options to 'Best Attempt', they were originaly at 'Require if certificate indicates

If you are going to copy and paste my solution, please do it on another discussion page/question. I don't mind if you share what I posted around the internet, just not on the same discussion.

I had the same issue, this resolution worked great for me. Thank you.

Thanks for all your replies, I had something deeply wrong with my ability to read my HDD.. Had my first appointment with the "Genius Bar" at Norwich store since purchase of my Mac and had a most interesting and successful time..🙂

Now this problem is solved if you install updates after installing Mavericks. Go to App Store | Updates | Install all updates.

This is better than the workaround of disabling some certificate security features.

This did it for me as well. Dunno if there's a security risk in doing it, but it got me past the hurdle, thanx!!

Thank you p1991atric

Without Apple fixing ocspd, you won't get past the issue without changing certificate settings in the keychain. The real problem is, that ocspd does a very bad job in retrieving OCSP or CRLs. While for example Firefox does verify all certificates sorrowfully on its own, Safari currently has problems with every second domain due to always the same error, that the CRL of the issuer could not be verified. This really effects about everything, for example I could not sign in to icloud on Mavericks, because the SSL certificates were not verified in the background. But it also does not help at all, if this only says "You can't sign in. Try later" and you need the console to find out what was happening. Trusting all issuers derived from root level CAs does not help really, because than you abandon CRL checking completely forever for the issuers.

Really fixing ocspd to do a much better job in retrieving and verifying OCSP sites and CRLs would help with A LOT OF current problems on OS X Mavericks.