Hi William, I just noticed your post, sorry. Go to the Support site, then click on Mathcad, then if you are a single user, click on single user, then contacts. You'll wind up on this page, which you can go to directly, but I want to help you and others find it in the future. If you have a license file, I suggest storing it in a separate folder. I store mine in my downloads folder, so I can find it, everytime I do a repair of Mathcad. http://www.ptc.com/support/mathcad_contacts.htm Best, Mona