iCloud Unknown Error

Recently I updated my Mac OS to Catalina when I got MacBook Pro 2017. Initially, I transferred my OS and data by using Time Machine. Then updated OS from Mojave to Catalina.

The first thing I realize was iCloud error: I could not make connection to my iCloud. The error message is "An unknown error occurred".

I tried to search for solutions on web. I could not find a good way to resolve it. I tried to ask Apple on-line help. They could not resolve it neither. At the end of the help, an senior manager asked to reinstall Mac OS by press Command + R key during restart. It took long time, about 2 hours to reinstall OS. Still I had the same issue after OS update.

The issue looks like something wrong within my user account and OS. It did not reach out to iCould service. I verified my iCloud in Safari, and it works fine.

Finally, I found a suggestion from an article on web (actually, the solutions in the article do not work, and only one in the comments is working). It recommends to clean my keychain folder. I was hesitant to take this strategy since I was worried about I could lose all my password and certificate settings. I spent several days already and with no luck. I decided to give it a try.

Here is the keychain folder I have to clean:

~/Library/Keychains/

After clean up, I did not see this message again. It took very long time complete the setup. Fortunately, I had my keychain in iCloud. After the process, my most passwords are recovered from my keychain in iCloud.

References

• OSXDaily article: Fixing iCloud "Unknown error occurred"