Outlook Mac Sync Pending For This Folder

Most of us have run into OneDrive for Business synchronization problems. Total storage limits, invalid file name. Outlook for Mac, which uses EWS, seems to choke hard when a folder within a mailbox gets too many individual items in them, especially Inbox. Outlook 2011 was downright terrible, I saw it happen with as few as 1000-2000. Outlook 2016 is significantly better, but I have seen it do sort of the same thing.

I posted this question on the Office 365 for Mac forum and was direct here. Any feedback is greatly appreciated. I've found several topics CLOSE to my issue, but none that fit it perfectly. I am an Outlook for Mac user with a MacBook Pro and using Office 365 for our Exchange hosting. Last Friday, I was running Outlook for Mac 2011 and I had an issue where my Inbox wouldn't sync. I only got the message 'Sync pending for this folder' in the bottom right of the screen next to the Connected status. At that point, the only thing I could do was quit/restart Outlook to get it to sync.

After some research, on Monday morning upgraded Outlook for Mac 2011 to the latest version (14.4.7 I believe) and updated my Mac OS to make sure that I had the latest updates to both packages. Still had the same issue. Today, I found Outlook for Mac (the Office 365 edition) and I running that (v.15.4) but I STILL have the 'Sync pending this folder' message and it's not updating. To date, the only solution that works is to Go to the Outlook menu and click 'Work Offline' then, a few seconds later, click it again to go back online. The only solution that I've seen but haven't tried is to 'Disable EWS Digest Authentication' but I don't know how to do that via Office 365 hosting.

Thanks in advance for any help/ideas.

• File Uploader • • PasteBin • • Knowledge Base • • Subreddits • • • • • • • • • • • • • • • • Infections • • • Tools • Software • • • • • • • • • Tutorials • • Please use the 'Select Flair' button after making your thread. Sort by: or Check out our, all guides are compiled by our Trusted Techs. Ask us here at, and try to help others with their problems as well! Please include your system specs, such as Windows/Linux/Mac version/build, model numbers, troubleshooting steps, symptoms, etc. The subreddit is only for support with tech issues. Please be as specific as possible.

After solving your problem, please mark it as solved by clicking 'flair' and confirming the 'solved' tag. Try to research your issue before posting, don't be vague. State everything you have tried and all the guides/tutorials/sites you have followed as well as why they were unsuccessful.

Do everything you can to reduce the effort of the wonderful folks offering to help you. No [Meta] posts about jobs on tech support, only about the subreddit itself. The following posts are not allowed: Password issues, posts without sufficient description (just title/link), posts offering rewards/compensation for solutions, PSAs or solutions already found, and anything that violates other's privacy or breaks terms and agreements. We are not a review site.

Don't ask us to compare or recommend products. Do not compare or recommend products. Keep all communication public, on the subreddit.

Private messages and other services are unsafe as they cannot be monitored. 24 hours between posts to the subreddit is the absolute minimum. No soliciting of any kind. This includes asking for us to link to your subreddit, forum, bulletin board, newsgroup, Facebook page, whatever. Products, services, surveys, websites - we're here to help with technical issues, not market for others. Employees of companies with social media presences for marketing or damage control are not allowed.