We have a software that add add-in in excel. We were using office 2010.No we upgraded that to office 2016 and the add-in is gone. When we try to add the add-in manually we are getting error Error:1004: Programatic access to visual basic project is not trusted. I am adding the add-in manually. Is there any command or registry hack so that we can make a script to add the add-in. The addin is located in software folder located in c drive.