Mail and Exchange email aliases problem

I'm running a completely clean install of OSX 10.8. and have a problem in Mail with Exchange email aliases.

When running Mail for the first time I had to login to the Exchange server using my domain username which is different to my preferred email alias. Now, when I "reply-all" to an email thread, Mail doesn't register that one of the recipients is myself under a different alias, so it's CC'ing me via one of my aliases. So it's a little annoying. It also means I can't send email and set the "From:" field as any of my aliases except the one Exhcange domain username.

Interestingly that doesn't happen and is fine on another Mac after upgrading it from 10.7 to 10.8 using the same Exchange account. Which might make some sense if it's inheriting legacy configuration compared to a clean install.

So how do I resolve or add aliases in my fresh install of 10.8?

Well I appear to have fixed it by doing the following.

Edit ~/Library/Mail/V2/MailData/Accounts.plist

Find the following key:

Add adding the aliases in something like this:


Seems to work exactly as I'd expect and it populates the email addresses in Mail Preferences for the account as you'd see for iCloud account aliases.

Why you can't change this through Mail Preferences I cannot fathom.

Because it doesn't let you, it's greyed out.