For several months now I´ve experienced severe problems with my mac. A few months ago we sent in our comp to the place we bought it planning to use our AppleCare warranty. Thay said it was a software error and gave us a bill. After that the problems remained. I get constant HD errors and constant freezes. I reformatted the drive 2-3 weeks ago and I have gotten errors not repariable by Disk First Aid twice. TechTool deluxe on the AppleCare cd fixes the errors not D.F.A can not but there´re still errors remaining. D.F.A claims to be able to repair them but after repairing once you get other errors and repairing a few times more will get you the error you began with. With TechTool you can repair how many tiems youo want, it says it has repaired them, but if you run it again it still need to repair. When dowloading files from the internet I often get corrupt files. I get errors in .sit files etc. etc. Disk Images seem to work somewhat but not 100%. Now comes the question, is this a hardware error with the HD and should I replace it or do you think it´s a problem with my software?