Apple ID on El Capitan does not work at all

This was a lifesaver. I was having tons of problems with iTunes, Safari, iCloud, etc. after installing El Capitan and this seems to have fixed it, even after a restart. Apple Chat was on the phone with me for hours and couldn't do anything except recommend I clear my hard drive and install the OSX all over. Huge thanks!

yup mine too, man im not sure what to do now? i click download all, and the wheel just spins in the upper left hand corner near the arrows in the app store.... click update all, they turn grey, then just go back saying update and u can click on them and nada

My problem is similar but a bit different I have two accounts on my iMac, my wife’s account works perfect. Mine is messed up.

I can log into iTunes and the iStore just fine, but my iCloud settings in preferences are a total mess. In the accounts it shows my iCloud accounts as inactive and there is no way they can be activated.

The iCloud settings are unchecked and when I check them they uncheck themselves. No way to save anything there.

I have the feeling this maybe related to, that I am running my account linked to a 2T hard drive and the daily operations of the two mac accounts for speed purpose running off a 250 Gig Apple SSD drive.

So my iCloud drive settings, messenger and iCloud mail are not working properly. I set up mac mail by getting it up as ‘Other Mail’ and that works.

Here is the kicker, I created a new user for myself on the SSD drive and everything works fine there. I might move and link everything to my new user account and get rid of the old one.

I have been scanning all posts but have not seen my problem occur with anybody else. Lot’s of mail problems and fixable login problems. But not grayed out accounts.

THIS WORKED.

My issue - hangs while trying to sign in to Apple Store, whether in App Store or iTunes.

My serial number was fine and visible in the About This Mac....

I was not hopeful, but aPenguin's fix worked like a charm. Immediately able to sign in and see all updates and previous purchases.

THANK YOU.

I'm having this problem when I try using Apple's bug report page and also when trying to use apps bought from the App Store. I get a pop-up message telling me I bought them on another computer (which I didn't) and that I have to sign into my Apple account to be able to use them, but it won't let me type in my password! I'm also fed up with iTunes freezing and having to be force quit. Then there's the lack of sound in Mail (apart from the whoosh when I send a message) and the same problem in iCal. I don't care much about the Mail problem, but I NEED sound when iCal sends me a reminder because there's a good chance I'm right at the other end of the house. I'm seriously thinking of returning to Yosemite. I had no problems with that.

After installing the OS X 10.11.2 update yesterday, the App Store sits with a blank window and a rotating activity indicator in the upper-left-hand corner. aPenguin's instructions made no difference, though I did have to re-enable accounts for Mail and tell iCloud to resume syncing Contacts and Calendar items.

I tried logging in with another admin account. The App Store worked fine there.

I rebooted in safe mode (space bar held down during boot). This took a very long time and never displayed the Finder screen, so I shut off the machine (held the power button until it shut off) and restarted NOT in safe mode. Again took a long time to boot, but eventually made it this time, and now the App Store works. Go figure.

Went along to the Apple Store last Monday as the Serial Number wasn't loaded when I had a new logic board fitted 2 years ago. As soon as the serial number was in, everything worked with logging into iTunes, AppStore, iCloud etc.

I am having the same problem on my iMac at work. The problem is resistant to rebooting in Safe Mode and to a PRAM reset. I am becoming convinced that El Capitan is a covert recruiting device for Windows. I have never had more grief from a OS "upgrade".

dude, I would really appreciate your help. I deleted iCloud Account files and the folder. So this folder can't be found again (Users/**********/Library/Application Support/iCloud/Account) What do I do

While this helped me immediately, it was not lasting after reboot (as others mention below).
In fact, my missing serial number was the source of the problem and the link Magicmogwai provided did help.
Thanks all!

I tried both solutions here. The solution by means of Terminal function worked first time when upgrading to El Capitan, but today had again the same problem that any application that requires signing to iCloud accounts (I Tunes, FaceTime) gets hung in signing in process and then have no otters option by to force shut the computer to close that application. I tried signing through the internet options proposed and the computer is hung signing in again. I don't understand why the heck an operating system upgrade should create such problems. I bought Apple computer and products precisely because they advertise a close system avoids all this crap.....

Thank you! I was able to login to my appleID online, in iTunes and App Store on my iPhone and MacbookPro but not my iMac with El Capitan on it. After hours of combing though threads and trying everything in the world, except for maybe squeezing goat testicles while chanting incantations around a smoky fire, that administrator sudo code fixed it! Thank You, thank you, thank you!

The sudo command solution worked for me but only until I rebooted my iMac. After the first reboot my Apple ID login to App Store hangs again. BTW my iMac lost S/N after installing El Capitan ("Serial Number Unavailable"). My case is currently handled by an Apple Senior Advisor and will post my solution update here when available.