Thanks Steve,
The message from Apple support- combo updates is: 'OS X Yosemite 10.10.3 Supplemental Update can't be installed on this disk. This volume does not meet the requirements for this update'. WHAT does that mean?
Beveller.
We can end the discussion, but I wanted to say that the failure to install is not a failure of Apple, but something in your system. Millions of users have successfully performed that update. DU doesn't do an exhaustive check of the drive, so getting that message is not authoritative. As it says, the drive "appears to be OK." Not that it is fully OK, but to DU it appears that way. There are failure modes of drives that DU is not designed to detect, but which will interfere with system installation. I'd suggest you do a full backup and keep it current. That drive is most likely going to fail soon.Disk Utility indicates "the volume Macintosh HD appears to be OK". Let's end this thread. As a layman computer user the fact that Apple sends a notification of an update then invites click on download then does not install is sadly disappointing.
But updating an application, which I presume was the "other successful updates" is not as intrusive as updating the operating system. Which is why a drive can appear to be just fine until along comes an update to the OS and you get an error about it.I just recently installed a Seagate 1TB USB 3.0 portable drive for back-up. Maybe that caused the trouble. I shall keep it up to date and await the fateful drive failure. That will make it the third drive that i have destroyed. One Microsoft XP. One Linux Ubuntu and now this. I have done other successful updates since this problem with OS X 10.10.3.
I was having a similar problem with the 10.10.3 download that Beveller had. Tried 3 times from the App Store with no luck. Tried the 10.10.3 Combo Update suggested by Bobtomay above and it worked no problem. Thanks Bobtomay.
2GB calculated to take 24 hours. This is an iMac with 960GB of available hard drive space. Difficult to understand why it should be giving trouble.
Oh my gosh! what does all that mean?.