I did a fresh new reinstall of Mac OS given when I got my Retina iMac it had 10.10.2 and not 10.10.3 well there was 3 or 4 updates I believe in the App Store for me to download however I have a question, after the 3 or 4 updates were installed the computer restarted and when it to the App Store window it said it was unable to connect to the store. Could this mean the updates didn't install successfully? in the App Store it says the updates "Installed" but given that the App Store wasn't able to connect after the restart of the install I was a bit curious if anyone here would know for sure that all is well and fine.