Quote Originally Posted by Djblois
Yes. My users should be able to change their settings. Why can't you overwrite an option in the personal workbook? Also, if I use a seperate xls file on the server for each user-wouldn't my add-in have to open that file each time it needed to access those settings?
I wouldn't store a personal.xls on the server for each user.

Two other options you have:
-Registry keys (GetSetting and SaveSetting). This stores the keys for each user in their registry.
-If you're going the external file route, personally I'd use a database for this. I've done this with a couple of my add-ins and it works quite well. The db is then stored on the server. The advantages of the db are that it permits multiple users reading/writing to it at the same time, which can be a challenge when using Excel workbooks.