You may see some or all of the following messages:
“[Number] of your items could not be uploaded and will need to be manually recreated in iCloud.”
After this message you will see a list of the contacts, calendar events, or tasks that could not be copied from Outlook to iCloud. Sometimes those items were originally created in an earlier version of Outlook that used a file format not compatible with iCloud. Sometimes the items have damaged or unrecognizable data. To fix the issue, create a new version of that contact, calendar event, or task in Outlook. During the next automatic iCloud update, that item will be added to iCloud. You can choose to keep or delete items that can't be uploaded.
“The following items could not be uploaded to iCloud.”
If you have contacts, calendar events, or tasks in Outlook that are duplicates of those in iCloud, and the iCloud versions are newer, the setup process will not overwrite them. You will be asked if you would like to keep or delete the versions currently in Outlook.
“Set up is complete. Could not upload [number] items. These items have been saved in local folders.”
You will see this message only if you clicked Keep when responding to either of the messages above. If you clicked delete, you will see "Set up is complete." These messages confirm that you can now use iCloud with Outlook.
You may wish to manually create new versions of the items that didn't copy to iCloud, and review any duplicate items that you chose to keep. In the iCloud folder of Outlook, the items that you chose to keep will appear in folders named "Local Calendar", "Local Contacts" and 'Local Tasks".
Note: During setup, the contacts, calendars, and tasks in your default Outlook Data File are copied from Outlook to iCloud. The original contacts, calendars, and tasks are then moved to your Deleted Items folder to prevent duplicates.