How to remove old identities from Mail? I previously had four e-mail accounts (and thus four identities) set up in the Mail app. I have now removed two of these accounts but when I compose a new e-mail the "From" drop-down box still lists four identities.

How do I remove the identities from the removed accounts?
Apparently removing the file
~/Saved Application State/com.apple.mail.savedState
resolved Daniel's problem without resorting to a factory reset.
Mac OS X is great for saving your progress but once in a while that savedState file causes these types of problems.
Happy Day!