Write an article based on this "Download and install iCloud on your computer if Outlook fails to sync properly with your iPhone. Verify that your iPhone has the iCloud feature enabled if you are using iCloud to sync your devices. Try refreshing your sync settings in iTunes."
iCloud can be effective at helping you manage and update information across all iOS devices that are synced with Outlook. Tap on “Settings,” then tap on “iCloud” on your iPhone. Toggle “iCloud” to “On.”  Place a checkmark next to “Calendars.” Outlook will now sync effectively with your iPhone. In some cases, you may need to disable, and reenable the Outlook sync feature.  Connect your iPhone to your computer using a USB cable. iTunes will automatically launch upon recognizing your device. Click on your iPhone in the left sidebar of iTunes. Click on the “Info” tab. Remove the checkmark next to “Outlook,” then click on “Sync.” Wait for syncing to complete, then place a checkmark next to “Outlook.” Click on “Sync.” Your Outlook calendar will now be freshly synced with your iPhone.