Resolve Commerce Category CSV Import results to error: “An unexpected error has occurred”

Scenario:

There are instances that the user is implementing a CSV Import of Commerce Category with Items and the response is always error “An unexpected error has occurred” without having any indicated cause.

Solution:

1. Navigate to Lists > Accounting > Items
2. Beside Item record: Click Edit 
3. Click Web Store tab 
4. Display in Web Store: Enter Checkmark
5. Click Save