Before I installed my copy of Lion, I started the migration assistant app Apple offered. But after installing Lion, I could not use mail.app at all. It starts by importing mails, then optimizing. the optimization fails and I get a message to start mail again and it will fix it. about 20 times and still nothing. I tried few tips I saw online, like removing the accounts from Mail, Contacts & Calendars. Still nothing. I tried to look for mail preference files but beside Stationery library I can't find anything. This morning I installed 10.7.1 from the website (Client) but I still get the same procedure. Open mail ---> import messages ---> optimize ----> fail ---> start mail again. Any one got any idea on how to fix this problem? I don't like web interfaces.