Brand new iMac, cannot login to anything I received my brand new iMac today. During installation/startup, I was surprised to find that I could not log in to iCloud. I skipped, figuring it was a minor glitch and I would do it after setting up the new computer account.

I have discovered that I cannot log on to anything on this brand new computer. I get a different error phrasing with each app, but they all basically state that "An unknown error occurred." I contacted Apple, got bumped to level 2 support, and now we are working with engineering to diagnose. I thought I would see if anyone has any other ideas or similar experiences.

Here is what I know:


This started from the moment I turned the computer on for the first time, where you initially are supposed to login to iCloud.
I cannot login to iCloud, iTunes, or the App Store from this iMac.
When I login, each app gives a slightly different error message but they are all consistent.
When I login, I get a spinning "wait" icon that lasts about 20-30 seconds, then a message comes up.


Apple app store and iTunes store says "an unknown error occurred".
iCloud says "Verification failed. An unknown error occurred."

I can login to both icloud.com and appleid.apple.com on the new iMac without a problem.
I can login to all of these apps on my Macbook Pro without a problem.
I can login to all of these apps on my iPad 2 and iPhone 6 without a problem.
My wife cannot login to her own app accounts on this new iMac computer.
I tried booting into safe mode, still could not login to anything.
Apple support had me make a secondary "test" account on the new iMac, still could not log in from there.
I have tried wired ethernet, home WiFi, and AT&amp;T cellular WiFi via iPhone personal hotspot -- same problems.
I reset the computer, and also reset the router and modem, no dice.
We ran Disk Utility, no problems.
I tried changing the computer date to one day ahead, this did not help.
We reinstalled MacOS, that did not work.


Any help or insight would be tremendously appreciated. Fair warning, I have a duplicate post on the Apple forums just to broaden my net, sorry if that is inappropriate in any way.
I've had this a number of times after installing a new copy of OSX, sometimes I was able to link to iCloud etc subsequent to install but ALWAYS with other problems that came up later, it never cleaned everything up to be working 100%. I also spent a lot of time and effort with second level AppleCare to no avail.

The ONLY successful solution I found, unfortunately, was to clean install over and over until it went through successfully. This often had to wait a number of days.

Personally, I suspect network issues which Apple were unable to pin down.

Eventually, all the computers I had issues with (which included a brand new iMac) worked and have worked ever since - about 2 years (Plus one 6 months ago).

Good Luck!

Paul.