How do I disable smart quotes, apostrophes in Mac Outlook 2011?

You can turn Smart Quotes off by unchecking "Smart Quotes" under Edit > Substitutions > Smart Quotes

The Mac has global settings for smart quotes. Even if you click them off in Outlook's Edit > Substitutions menu, you may still get them in your email.

With an email open, go

Edit > Substitutions > Show Substitutions > Text Preferences

that takes you straight to the global

System Preferences > Keyboard > Text

where there is a global option to turn smarties off. You may also be able to go directly to System Prefs from the Finder, and they may stick in Outlook. I am hedging because I remember doing this a while back, but I just checked and they're magically turned back on. I don't know when or how that might have happened. One must be ever-vigilant against attacks of the Zombie Smart Quotes!