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Like many of you, I have more than one e-mail account set up in Mail. I've got my work account at Macworld, my work account at macosxhints, and then a few assorted personal addresses that I use for various things. When composing a new e-mail, I can pick any of these sending accounts using the From drop-down menu in the new message window. You control the default sending account for new messages using the Send New Mail From drop-down menu in the Composing tab of Mail's preferences; I have mine set to "Account of last-viewed mailbox.
Even with the preference set to use my last-viewed mailbox, though, there are times when I want to change the sending account. Until recently, that required either reaching for the mouse, or judicious use of the Tab and arrow keys to select a different sending account. Now, however, I can change my sending account using a simple keyboard combo. What magical third-party application enables this bit of trickery? None at all-it's built right into OS X in the form of the Keyboard Shortcuts tab of the Keyboard and Mouse System Preferences panel. (Note that this has only been tested in OS X 10.5, and I don't think it will work in 10.4.)
As it turns out, you can define shortcuts on that tab for each of your sending accounts. There's nothing really tricky about it, either, other than making sure you specify the menu item exactly as it's formatted in the drop-down menu. Assuming you used your full name when creating each account, the standard format for each entry in the menu is:
Firstname Lastname <user@host.address> You can, obviously, see exactly how each of your e-mail addresses are formatted by simply activating the From drop-down menu in Mail. On the Keyboard Shortcuts tab, click the Plus sign, and set the Application drop-down menu to Mail. In the Menu Title field, enter the details for the sending account, exactly as they appear in Mail's drop-down menu.
Click in the Keyboard Shortcut box, then press your desired shortcut. To avoid conflicts with existing Mail keyboard shortcuts, I recommend using the Control key, either alone or in combination with Command, Option, and/or Shift. When done, click Add. Repeat for each account for which you'd like to create a shortcut.
Switch back to Mail, press Command-N to start a new e-mail, and press one of your newly-defined keyboard shortcuts. When you press the shortcuts, you should see the From drop-down menu change to the chosen account-even though the menu's not technically active, then sending account will still change when you press the shortcut.
As you can see in the image at right, the menu will even show you your shortcuts, in case you happen to forget them. As an added bonus hint, it turns out you can use this same technique to create keyboard shortcuts for both the SMTP Server and Signature drop-down menus as well. So if you use a lot of signatures, you can easily keep your most-used options no more than a keyboard shortcut away. Just remember to precisely match what you see in the menu (capitalization counts) in the Keyboard Shortcuts panel.
I've found this to be a tremendous timesaver-so much so that I've duplicated it on all three Macs I routinely use, and have become very used to switching the sending account with the keyboard.
Read article at Macworld.com