Considerations while reading/writing registry keys under HKLM from Office Addin in Office Click-to-Run

An add-in running on Click-to-Run (C2R) version of Office (Office 365), which creates custom registry entries under HKLM hive, will have the registry entries created in the C2R portion of the registry . For example, if your add-in tries to create a registry entry HKLM\Software\MyCustomKey then it gets created as HKLM\SOFTWARE\Microsoft\Office\ClickToRun\REGISTRY\MACHINE\Software\Wow6432Node\MyCustomKey (Wow6432Node assuming 32-bit Office). This is by design as C2R…


After installing Office 2016 Version 1609 Office files containing VBA Form may hang the Office application [Update: Fixed in Office 2016, 1610 build]

Issue If an Office file has a UserForm which has Cycle Property set to “2 – fmCycleCurrentForm” (or any other control which has this property set) then the Office application may hang while trying to show this UserForm in Office 2016 Version 1609. Cause This is a bug which is being worked by Product group….

VSTO Add-in may fail to load if signed by some SHA256 certificates [Update : Fixed with latest VSTO runtime]

Symptom VSTO add-in may fail to load if all of the following conditions are true:- The SHA256 certificate used to sign the add-in is based on SHA256 algorithm ( “Require Add-ins to be signed by Trusted publisher” setting is checked in Office Trust Center. The deployment manifest is not accessible (For e.g. you installed the VSTO…