Connecting to Apple iCloud
Apple accounts can sometimes be a little awkward to connect to. There have been a number of changes from Apple over recent years.
The most important is that the require an “app-specific password”.
The second to check is that your calendar is accessible from iCloud.com.
1. App-Specific Password
To connect to Apple iCloud you will need to generate an app-specific password and use that instead of your regular one. They look something like this
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You will need to enable multi-factor authentication for your account if you haven’t done so already.
Apple’s help article on how to do set this up can be found here: https://support.apple.com/HT204397
As of June 15 2017, Apple required that all applications use app-specific passwords when connecting to iCloud services. Therefore generating an app-specific password became mandatory when previously your regular password may have worked.
2. Check the Calendar on iCloud.com
You should also check that you can access your calendar at https://www.icloud.com/ Sometimes Apple require some further verification before they make your calendar accessible through your iCloud account.