Created Unassigned: Import Items Failure [5]

I have been attempting to build a catalog with the Import feature. I keep getting file not in expected format message. As I am a novice (not a newbe) does someone have a link to information with more details on how to make this process successfully work?

I am using Office 2013
Chrome Browser or IE 32 or IE 64
Built on a test machine using web matrix 3

Thank You