iCloud and my default folder
How to sync my iCloud items with my Outlook default folder?
Make sure the left hand Navigation Bar is fully enlarged (View - Navigation Pane - Normal).Click "Folder List" to ensure all folders are clearly shown (expand them if necessary).Work out which folders are your Outlook default/primary/master folders. This can be shown as follows: Right-click the folder, then click "Properties". If there is a tab called "OLMixedFolders" this is NOT your Outlook default/primary/master folder.
Example of setting up synchronisation using Calendar
Right-click one of the non-default folders at the top, e.g. "My Calendars"
Click "OLMixedFolders" tab
Tick "Synchronise this folder"
Decide: Do you want to be able to change items on either device and the change be copied to the other? If so, tick "Changes in both directions"
The next box down shows the category wich will be used internally with OLMixedFolders as a name for the sync-job.
For simplicity, and for the time being, untick all the synchronisation options in the lower half of the screen.
[Thanks to Ted, who has made this tutorial]