How do I prevent Outlook 365 on the Mac from launching the New Version

Hi Diana,

This document covers Outlook preferences on the Mac, and explains the Enable New Outlook functionality. It's best to think of this as a hidden button in Outlook > Preferences, rather than a "work around".

At a very basic level, Outlook stores your settings in one folder, your Outlook Profile data in another, and your application data in a third place - the command used here does not directly affect anything in your Profile and I wouldn't expect any problems.

I posted this earlier, but its worth posting again as a fix to this Microsoft Office update problem on the Mac:

1. Open Terminal
2. Type in:

defaults write com.microsoft.Outlook EnableNewOutlook -int 0 

3. hit enter

Outlook will cease to try and update itself.

To re-enable:

defaults write com.microsoft.Outlook EnableNewOutlook -int 1 

Recently this happened on my wife's computer and the only way to fix all the misplaced emails located on the client computer was to restore the database folder using Time Machine:

/Users/username/Library/Group Containers/UBF8T346G9.Office

It's absolutely incredible that Microsoft is subjecting its customers to this kind of negligence.

Good luck!

Just to add to the dissatisfaction over this new Outlook for Mac. It is awful, it automatically opened a few weeks ago and left me with the same symptoms as others: all calendar entries had disappeared, email folders scattered all over the place, extremely limited viewing options on email lists. Absolutely awful. I reverted to old Mac and, thank god, all was OK. And now my Outlook is telling me that it will auto-open the new Outlook next time I restart. Who the hell do MS think they are? Offer me the option by all means, but don't force this **** on me. I don't need to be told by MS what I do and do not need to do with MY computer.

Knowing the past history of MS when it comes to end user complaints, I would be very surprised if they will listen to any of us on this forum. They will continue to do what they want to do.

I agree. This is extremely frustrating. Each time Outlook has, on its own, switched me to New Outlook, I have lost emails. The missing emails do not appear in my Deleted Items folder, my Archive, or anywhere else. I don't trust New Outlook at all. But every time I turn off New Outlook and then update Outlook, it automatically starts in New Outlook and emails once again disappear from my inbox.

Microsoft, you need to fix New Outlook!