What many people suspected might happen has happened: Business Contact Manager (BCM) will not be updated to work with Outlook 2016. Anyone who uses Outlook 2013 and wants to continue using BCM will need to remain on Outlook 2013. This means BCM users should not update to Office 2016 this week and will need to block the automatic updates that are coming October 1 2015 for Office 365 Personal, Home, and University. (Business subscribers will be automatically upgraded at a later date.)
It's very important that BCM users do not upgrade to Office 2016. They will also need to block the automatic upgrades to prevent Office 365 subscriptions from automatically upgrading to Office 2016.
Businesses using Group Policy can block the automatic updates using the updated Office 2013 group policy template. Look for the option to block updates under Computer Configuration\Administrative Templates\Microsoft Office 2013 (Machine)\Updates.
Double click on Enable Automatic Upgrade and choose Disabled, then click Apply and close the dialog. If Outlook is open, close and restart it.
Anyone can block the updates by setting the following registry key (create the keys if they are missing):
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\office\15.0\common\officeupdate
DWORD: enableautomaticupgrade
Value: 0
You'll need to close and restart Outlook for values under the policy key to apply.
Do It For Me
If you don't want to edit the registry yourself, you can download this ready-to-use registry file. Double click to run. enableautomaticupgrade
More Information
Users who were auto-upgraded to Office 2016 from Office 365 Personal, Home, or University who need to revert back to Outlook 2013 will need to contact Microsoft support by selecting Contact Answer Desk on the Microsoft support page.
Business subscribers should have time to block the upgrade using the registry key, if not, see Obtaining older versions of Office for the steps necessary to revert to Office 2013.
Published September 22, 2015. Last updated on October 23, 2020.