My wife still uses QB 2003 basic edition to book-keep for a friends companies. We have been running it on successive versions of C/O for several years (Linux version). Following a breakdown we bought a new computer and installed C/O 11 and copied over the old "win 98" bottle. It fell over, with a message about needing a gecko browser. Various attempted fixes did not work. The problem is that QB 2003 is very tightly integrated with Internet Explorer 6 and when that is broken so is Quickbooks. The easy fix was to download the last of the version 10 editions of crossover (10.2.0 Pro) and that works as expected (previously had 10.0.3).