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Will users need to install anything locally?
" Yes. I've some experience creating and deploying VSTO's. These addins are installed manually. The few ones I made were Controls (visual components with graphics in it) and some Excel Basic function extensions. You can define a Basic function in a VSTO. The sheet - or template - contains the basic code calling the VSTO. Buttons can be defined, to let the Excel create a graphics control on the sheet that is defined in the VSTO. It works for 365. But this is not without pitfalls. The validity of a VSTO depends on the Excel version installed. If you want to use VSTO, see you standardize your users on one version of excel, before trying to distribute your VSTO. Once your VSTO is installed, it can be replaced by a newer version if needed, by manually uninstalling it, leaving Excel, entering Excel again and install the new version of the VSTO. So, bottom line: nstead of these 130 sheets, your will worry about all these PC's that need to install your addin. An addin is not like a template on a share. It is NOT updated automatically of you correct errors in your VSTO code ! So in short, I'm afraid VSTO is not the solution to your problem. If you really want dynamic code support, use scripts instead, like Powershell or C-script. You could use Excel interop to generate sheets.. Anyway in the end this will give a version maintenance mess. What would be a solution.. is making an inventory of what you trying to visualize in these sheets, devise a data model, implement a database for all data involved. Then export views from that database and (only) visualise using VSTO. From Excel, you can access the database directly and queries are stored in the templates. Your data should reside in a central place, not in 130 Excel sheets. And yes alas.. this is an expensive project.
