iCloud login problem on Sierra, High Sierra? Try this.

Download the Apple Intermediate Certificates

Apple IST CA 2 - G1 - This is a download link, the certificate will appear in your downloads folder.

• Double click the downloaded certificate to install it in Keychain Access.

Try to log in to iCloud after that, should work.

I found my Keychain Access was unlocked. Should it be locked for normal operation?

Th below .cer worked on my Mac. But my iOS devices are still exhibiting the same issue having no access to iCloud and password errors.

Download the Apple Intermediate Certificates

• Apple IST CA 2 - G1 Certificate

https://www.apple.com/certificateauthority/AppleISTCA2G1.cer

I found my Keychain Access was unlocked. Should it be locked for normal operation?

Th below .cer worked on my Mac. But my iOS devices are still exhibiting the same issue having no access to iCloud and password errors.

Download the Apple Intermediate Certificates

• Apple IST CA 2 - G1 Certificate

https://www.apple.com/certificateauthority/AppleISTCA2G1.cer

pedrocaiano wrote:

So the dreaded day has come, the certificate has expired (as announced previously) and I'm right back to where I started.

iCloud has stoped working again.

SOLUTION: Open Keychain Access, Double click on the Apple IST CA 2 - G1 Certificate, Expand Trust option, When using this certificate: Select "Always Trust".

Restart the Mac.

Done!

this doesn't work for me, for example "cloud drive" doesn't sync on my Macbook Pro with High Sierra !

I think we need a renewed certificate from here Apple PKI - Apple

Just update the Apple IST CA 2 - G1 cert from the Apple PKI (Apple PKI - Apple) site as pedrocaino said.

I did nothing else on my Sierra installation (I did not use 'Always Trust' anywhere) but install this new cert. I then logged out of iCloud and then back in without issue. Note that I only use iCloud for Notes.

I CANNOT thank you enough! 😀 My iCloud, iMessage especially on my older Mac running Sierra just simply stopped working out of the blue (iPhone, iPad, Watch was fine)

5 days of silly messages of "You can't sign in at this time" "Update password" prompts and "Change Password" - which I did 3 times. ALSO other sites stating deleting Accounts, SysPref, etc failed. This solved it!

Again, much much thanks!

Just curious as to how did we suddenly lost or need this certificate and all these people running Sierra/High Sierra started getting this error... Do you think it's related with the software update Apple released on April 5th and their servers?

I tried it downloading the certificate, found out there were two:

AppleISTCA2G1.cer

AppleRootCA-G2.cer

Downloaded the two, seems to be in the Certificates list but opening Notes still the wheel keeps turning. Or do I need a restart of the iMAC?

Thanks to Pedrocaiano for pointing me here. I was skeptical because I could long in to iCloud using Safari on the MBP but not to iCloud. Any way I downloaded the certificate and hey presto I can connect to iCloud. After three days I was on the point of doing a clean install of OSX.

Add me to the list of people having this same issue. For me, it started on Apr 7, and after trying lots of solutions in Apr 8, and spending three hours on the phone with Apple, it looked like it was fixed by a reinstall of Sierra and removing/rebuilding the Keychain folder contents and the com.apple.system.preferences.plist file. (Now I am not sure why that worked if it was a certificate issue.)

It was fine until yesterday, when I got my monthly Apple ID lockout (since 2020, my AppleID started to lock me out periodically. It went from once every few months to monthly to weekly, disappeared for a long time, and then came back last Fall, locking me out once a month again. Many people complained about this problem on this forum and concluded that it's a problem with Apple's servers and had no relationship to the OS, or if someone used 2FA). And then nothing worked this time until I posted my own question and a kind person referred me to this certificate solution.

My expiration also says May, so this may be another monthly task, along with the lockout, unless they are related, and that is why all of my devices - old and new, supported and not - are locked out. Maybe they all need to re-certify and now the Sierra laptop can't on it's own because of an Apple server bug.

Thank you so much for this, as the not being able to sign in was driving me round the bend.

Now all my icloud stuff is working apart from the drive - when I select icloud drive in finder its just blank??? Any idea how I get it to see the cloud and repopulate all my stuff please???

I suppose you have to go to System Preferences -> iCloud -> iCloud Drive, Press options button, re-enable Desktop & Documents Folders and anything else you need back. It should fetch info from the cloud and re-populate.

THANK YOU! I was going nuts last few days. My 2009 MacBook Pro is running on MacOS 10.12. and was thinking if this iCloud thing doesn't resolve, then it's time get a new MacBook. however, I have old version of Photoshop and Lightroom that I have so much presets on. I just can't part with this almost 13 yrs told MacBook Pro yet! THANK You for everything and I hope the cert doesn't expire in a month or so.