Outlook for Mac 15.3 (Outlook 365) gets hung up on Sync Pending

Airborne -- I'm in the same place as you.  I have already converted nearly every PC in my company to Mac  hardware.  Now, I'm trying to replace MS software, but it's proving a little more difficult than the hardware.  

If you know of a resource where other like-minded switchers are finding support and collaborating on best practices, please let me (and I'm sure others on here) know about it.

Sorry to hear that.

All of my machines are working without any problems now. I have been looking for a solution that works for me for more than a year - as this problem plagued me from 2011 and is the reason I went to 365, which worked great, for a while...

I wish I could offer some advice, but being a Windows deserter, my Mac knowledge is at 101.

Hope you find a solution and wish me luck that this fix sticks past the two days it has been running.

Locate your account setup file here: ~/Library/Group Containers/xxxx.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/Exchange Accounts/xx/

(the file will not have any extension)

I am an experienced windows user that has switched to macs. All 3 of my macs have this problem, but i noticed that if i change the server, it works really well until auto discover changes the server reference - even though I am sometimes prompted to accept the change I decline, but the server is still modified.

My question was how do I locate my account set up file? For ex-windows users, who may not be familiar with macs, this is what you do:

1. Open outlook
2. Change the server
3. Quit outlook (as the auto discover can work at any time and you may lock the file in the wrong state)
4. Click on Spotlight Search the hour glass in the top right hand corner
5. Type in ~/Library/Group Containers/
6. Go through the directories until you come to the last folder indicated above.
7. The file will not have an extension but will end in "ExchangeAccount"
8. Right click on the file
9. Select "get Info"
10. check the "Locked" box
11. Open outlook

If you are prompted for a password, even though you know it is there and correct, maybe insert the server without the "https://" proceeding it, then repeat the steps above.

I did look at the file (copied it to my desktop and changed its extension to "txt" and notices that it has a call to auto discover - i suppose that this "fix" does not allow it to happen.

Actually seems to be working and as changing the server always worked (but was tedious) i have high hopes for this fix. This sometimes used to happen with my iPhone and iPad when auto discover would change the server name. For this fix I will reserve judgement as I have been struggling with this for months with both 365 and 2011.

PS, Up to 2 days & this seems to be working - it has not done that before...

Excuse my ignorance but what do I change the server to?

The address of the server that is used when you set up the account. In my case was something like email.mycompany.net.

I read and tried many of the solutions to the sync issue people have suggested. None of which worked (turning on logging, locking the files etc). 

However, i've solved for it for myself today, so I thought I'd tell you all what I did in the hope it might work for you too...

I opened Outlook in Windows (you could use OWA I guess) and complety emptied all subfolders in the "Sync Issues" folder. So empty out the "Conflicts", "Local Failures", "Server Failures" folders. Then I re-opened my Outlook 2016 on the Mac and the sync issue pending annoyance is gone and mail is arriving without a shutdown-restart.  

Of course it might start again..in which case I'll repost..but for now it is working. The syncing process was obviously getting stuck..  

And: This is to a hosted Exchange server running Exchange 2010, not Office365. 

Hope this helps anyone in the face of this bugginess and lack of support from Microsoft (as usual)..

JB