Hmm... I once installed some version 5 or 6 on PC for testing purposes and it showed the "do you want me to associate..." dialog on every startup, as well as a "shut up" checkbox. Clicking "shut up" disposed of the dialogs and it did not associate with ZIPs. If the recent version no longer shows this option then it must be either a bug or really careless behaviour of the developers (worth the golden CL medal :-) In both cases you should contact the company and COMPLAIN. It is a small independent company with a good relation with their customers for many years, so I'd say it is worthwile to let them know about your problems. And by the way, SIT is a hell of a compression format. I am often trying out new compression formats, and SIT usually beats everything that I ever found. As a matter of fact, for every given compression scheme you can "construct" an artificial file that compresses perfectly, and another file that doesn't compress at all. But in real world tests, SIT is just great, especially with binary files that are hard to compress otherwise.