Perhaps attempt the install while in safe mode and see if that is successful. If I have missed something I hope someone else will jump in here and offer a suggestion.Įdit - You might try a restart in safe mode and let the iMac do cache cleaning and housekeeping. I apologize if my attempts to help have wasted your time. To that end, I've collected this link to the Mac OS X Mountain Lion retail purchase and download from the Apple Store. It may be that your original thoughts to download Mountain Lion and begin your upgrade from there were smack on target. And I believe your iMac meets the requirements for the upgrade. You have the links to the Apple Support documents detailing how to upgrade from Snow Leopard to El Capitan. You might try once more to download a fresh copy of 10.11 El Capitan after first deleting the current download. As reported by MacWorld, through support pages, it’s. As I see it you are following the instructions as presented in the support docs and I felt sure that the combination of available downloads would have been enough to get you to your destination here. Ten years ago, users needed to pay Apple 19.99 for the latest version of its OS X, and now you can finally download these two for free. Unfortunately I am unsure what the hang up is in this case and am at a loss as to how to proceed from this point.