Excel Add-in Question

I got this question from someone who saw my blog and thought it would be a good blog post:

"I hope this isn't a dumb question but it seems like if one user sends another user a spreadsheet with the Essbase add-in, it somehow installs itself. Then is a total mystery how to remove. It's not in Add-Remove programs or program files that I recall. Regedit? Any ideas?"

Due to the architecture of the Excel Essbase add-in, the add-in cannot possibly install itself from within an Excel workbook.. In fact, most people have trouble installing the add-in using the installer program as it requires admin privileges to install. That being said, one possibility is that the Excel add-in is already installed on your machine and the Excel workbook simply contains a Workbook_Open() macro that is setting the Excel AddIn.Installed property to true (to assure it is available).

If you have a Workbook_Open() macro, you used to be able to bypass it by holding down shift when you open the workbook. You could then go to the VBA editor (Alt-F11), choose the Workbook object and delete (or comment out) the code.