Multiple "From" addresses in mail.app using OS X Lion

Question

One nice feature when using IMAP within mail.app is the ability to list multiple addresses in the “email address” field separated by commas. This allows me to have both my real email address as well as any aliases defined. For instance, I might have username@domain.com as well as alias@domain.com separated by a comma. With this configured, if someone sends something to alias@domain.com, when I hit "reply-all" my alias is not listed in the To: or Cc: fields.

My company recently upgraded to Exchange 2010, and I've converted to using the "Exchange" account type to gain the additional integrations as well as calendaring. However, the problem is that now I no longer have the option to change or add additional addresses to the “email address” field in the Mail settings for the Exchange account. (It’s grayed out) Has anyone found a workaround for this issue?

Answer 1

Through some digging and a bit of luck, I've found a solution to this problem.

1. Shut down Mail.app
2. Edit /Users/<username>/Library/Mail/V2/MailData/Accounts.plist in your favorite editor.

3. Search for "EWSAccount" in the file, and you will see an XML structure similar to the following that contains the information for your particular setup, including the offending Exchange account.

   <key>AccountName</key>
   <string>Description</string>
   ...
   <key>EmailAddresses</key>
   <array>
   <string>username@domain.com</string>
   </array> 
   

4. Add your additional alias in the EmailAddresses array like the following:

   <key>AccountName</key>
   <string>Description</string>
   ...
   <key>EmailAddresses</key>
   <array>
   <string>username@domain.com</string>
   <string>alias@domain.com</string>
   </array> 
   

5. Save the file, restart mail, and all should be well! No more emails to yourself or your alias during a "Reply All".

Answer 2

Exchange sucks in this and, IMO, many other ways. At my companies' exchange server I have my "main" email address, plus about 10 aliases. I can receive mail from any of the aliases. But when I had my Exchange account configured as an IMAP server in Mail (even on SL and earlier) any time I sent, regardless of the from address I specify in my client, it is always converted on the Exchange server to be from my "main" address. It works exactly as you describe for all of my other account types, just not Exchange.