I ran into a problem installing QuickBooks a few days ago. I kept getting a popup message ending with “Interface not installed” whenever I tried to uninstall QuickBooks 2003 or 2004 Beta. Thinking it was a QuickBooks problem, I called QuickBooks support but they generally were not helpful except to say that I would have to re-install WinXP. That was not an acceptable solution so I started hunting around to see what I may have done to cause this. After a little more checking I noticed that IE was not opening a new window when I clicked on a link and NAV was not updating the virus files.. This was in addition to the problem I found with uninstalling QB. After a little bit of sleuthing I noticed that I uninstalled a free program called CDBurner Pro XP just prior to the upgrade. I used the system restore feature of WinXP to take me back to just prior to the uninstall and now everything works. I have upgraded to the production version of QuickBooks Pro 2004. Someday I will go back and fix this problem.