I've never had "too many" problems with Mail.app before, but recently (upon upgrading to DP2 I think) I haven't been able to filter my emails through the upper right search box. It works fine in spotlight - I can search for specific emails as usual. The deprecated search has led to another problem - my smart mailboxes don't work anymore! They won't show any emails that fit the rules! I've tried rebuilding, resetting envelop index (but Mail didn't rebuild one and crashed so I had to copy the original back - makes me wonder if it's something wrong with indexing?), removing my accounts from Internet Accounts and delete everything associated with Mail.app. None of these approaches worked. Is anybody else having problems with Mail? Could you try to use the filter function in Mail and share the results? Thanks!