I bought a Mac Pro (2009) desktop today off someone online. Everything seem to be alright with it, except I can't connect to a server. It says I am connected to the Internet after connection my airport to my modem, but when I try to open iTunes or safari it won't load. And if by some chance is does, there is either a DSN error or a -1001 error. Again, it says I am connected. I ran a diagnostic report and it says I can't connect to the server. I don't know why I can't connect it. I've done many things. I've re set my modem, restarted my computer, put in my IP address manually, but I am at a loss. I know this is a common problem, but I need a detailed step by step on how to fix it. If anyone has any advice it would be greatly appreciated as I am at my wits end with this machine. Thank you!