I have 10.3.9. I've installed all the updates to the OS, Itunes and everything. I know somebody who had 10.4 but doesn't use his old computer anymore. I want to take his copy of Tiger that came with his computer and use it to upgrade my computer. Can I do that, or will it not work because it was installed on another computer already? Am I likely to have any other problems upgrading to 10.4 and then installing all the relevant online updates?