Microsoft has released a 64 bit version of Office for Mac 2016 at August 22, 2016. Now it seems that 32-bit add-ons aren’t compatible and causes issues.
Mac OS: Office goes 64-bit
Microsoft decided to go to 64-bit on Mac OS and delivered an upgrade for Office for Mac 2016. But this destroys support for 32-bit add-ons. Now Microsoft released the support article Error messages after updating to Office for Mac 64-bit. User experiencing the following issues after upgrading to 64-bit.
When you launch Application, you receive an error message that reads: “Compile error in hidden module: ‘<name>’.”
This error commonly occurs when an add-in’s code is incompatible with the current version, platform, or architecture of Office 2016 for Mac.
Inside an Office 2016 for Mac application, you see the add-in buttons are greyed out.
Inside an Office 2016 for Mac application, your add-in buttons are missing from the ribbon.
This applies to Excel 2016 for Mac, Outlook 2016 for Mac, and PowerPoint 2016 for Mac. An add-on that may be causes problems is Adobe PDF Maker The partial solution is to turn off add-ons or a rollback to 32-bit Office for Mac 2016. But a rollback isn’t a long term solution, because Microsoft starts in September 2016 with global rollout of 64-Bit Office 2016 for Mac. Further details may be found also at KB3187505.