The Office 2016 for Mac Preview - June 23, 2015 update provides bug fixes for the Microsoft Office 2016 for Mac Suite (Word, Excel, PowerPoint, and Outlook). This update has some prerequisites.
How to obtain the update
Microsoft Download Center
This update is available for download and installation from the Microsoft Download Center:
To install this update, you must be running OS X Yosemite 10.10 or a later version.
Microsoft AutoUpdate for Mac
This update is also available from Microsoft AutoUpdate. AutoUpdate is provided together with Office. It automatically keeps Microsoft software up-to-date. To use AutoUpdate, start a Microsoft Office program, and then click Check for Updates on the Help menu.