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I have an aluminum iMac. Everything is very fast except the Mail application. When I click on Mail in the dock it bounces once but it takes about 8-10 seconds to open and the beach ball spins. When I click on anything in the tool bar menu there is a delay before the drop down menu opens, there is also a delay when I close mail. This is the only application I'm having this problem with, other more intensive programs don't have this problem. Is there anything I can do to fix it?

Do you have an enormous amount of email stored?

I'd start by dumping its cache and plist file.