In Excel and PowerPoint I can create an Add-in file (xlam, ppam) that with a customUI embedded will add a custom button to the Excel or PowerPoint menubar and allow me to execute the macro in the add-in.
Similar in Word I can create a Word Macro-enabled Templete file (dotm) that with a customUI embedded will add a custom button to my Word menubar and allow me to execute the macro in the templete file.
The Excel and PowerPoint add-in reside in the Microsoft/AddIns folder. The add-in need to be activated in the Excel options and PowerPoint options respectively. The Word templete resides in the Microsoft/Word/STARTUP folder and is added automatically to the menubar.
How about in Outlook?
I can create a macro in a New Mail Message window and execute it via the Developer tab.
But how do I create a New Mail Message add-in file?
And where do I need to put the add-in?
And is it possible to add a customUI script to the add-in file so that I can execute the macro from the menubar in every New Mail Message window?