Outlook Favorite Folders and Calendar Groups not syncing from Exchange Online

MartinHolstDk BenHendricksWC 

Here's what I did and so far and it's working.  I tried this fix before, but I didn't wait it out long enough for it to work, kept thinking Outlook froze after 20 minutes, and I would kill the process.

Here's what I did.

1. I had all users turn "Cached Exchange Mode" back on, and under "Cached Exchange Mode Setting" made sure all the check boxes were checked. 
2. I also turned off "Shared Calendar Improvements"  (not sure if this step is necessary, but I did it just to make sure)
3. Restart Outlook, then go to your public calendar properties, click on the Synchronization tab and check the "Statistics for this folder"  Make a note of the last sync date, mine was Jan 4, 7 days ago)
4. Click on the General tab, and click "Clear Offline items" (This is where I didn't wait long enough)
5. Wait for the process to finish, it will freeze windows, and look like Outlook is frozen, but it's not. Depending on the size of the calendar will determine how long it takes, I had to do two calendars, one took about 35 minutes and the other only 10), Even if the window comes up that it's finished and Outlook is still frozen, keep waiting, it's not done yet, but will be eventually. 
6. Once Outlook is finished and it's unfrozen, you can restart Outlook
7. Go back to the public calendar properties, click on the synchronization tab, and check the last sync date, it should be current and you should be good to go at this point.  

If you have more than one public calendar like I do, just repeat the steps for each one.  I also turned "Shared Calendar Improvements" back on for each user.  So far I've only tested minimal, but we can post something to the calendar and it will sync up with all the other users now.