Excel for Mac 2011: ComboBox Autofill

Dear Excel gurus - I have a list of over 500 names and I would like to create a combo box with the ability to pre fill in Excel. For example, when a user enters part of the value (say the first letter "a") within a cell, the combo box presents a drop only the names which begin with "a". Most importantly, I am using Excel for Mac 2011. I read some post on how to do this but discovered that the same features (and vba script that was provided) did not work in Excel for Mac.

Can you please guide me?

Many thanks.

The contexture.com post does not explain steps for Mac