One way around this problem is to use an automatically reversioning
addin loader.
You can download one from my website and tailor it to your
requirements. The password for the XLA is dm
http://www.decisionmodels.com/downloads.htm

regards
Charles

By doing this I should be able to overwrite the Add-In workbook to update
"bugs" that I find, without having everyone on the sales team close the
workbooks so I can do updates.