
Like I said, this works but only for a few weeks.
File > Options > Add-ins > Go > Add Button. Open Outlook as an administrator (Hold shift and right click, chose run as administrator). This is what I do to get it working again temporarily: I'm trying to find a permanent solutions. Every time this happens I can get it working by removing the add-in then manually adding it back into Outlook but then it fails again in a few weeks. I have a client that is using the iCloud Sync add-in for outlook to keep his calendar in sync between his phone and work calendars What happens is that things work great for a few weeks and then suddenly the Outlook Add-in will no longer load and syncing stops.