If you purchased an upgrade from FCE1 to FCE4 then you may need to have FCE1 installed on the new machine so that the upgrade has something to actually upgrade.
A call to 1-800-APPL should be able to answer you question.
How do you upgrade your software if you're switching from PowerPC to Intel Mac? I have a Final Cut Express 1.0.1 that I'm thinking of upgrading to FCE 4 and would like to know the proper way of doing it. I was told that you have to install the old version 1st then install the upgrade and another one said that you don't need to install the old one just the serial # from the previous version. Thanks for the help.