So I started downloading the 10.10.4 update last night on my MacBook, closed the lid and came back to it this morning to find an error message saying something about updates not installed correctly/couldn't be verified. But then it took me through the standard steps you go through to install a software update, like inputting your Apple ID password and choosing whether to set up iCloud Keychain etc. It seems I'm still on 10.10.3 though, despite this, after checking in About This Mac. Now when I go to the App Store Updates tab it still lists 10.10.4 (when I click Update on the right nothing happens), and the spinning wheel/Checking For updates goes on forever. Have tried restarting numerous times, but the same thing happens every time. Have also tried repairing disk permissions to see if that did any good, but nothing doing. Any ideas? Thanks for any help.