I am trying to import an mbox folder (from cpanel webmail) into Outlook for Mac 2011 (latest version)

When I select 'file, import folder' the mbox file i have downloaded from my webmail is greyed out so that I cannot select it to import.

I have checked the 'get info' properties and permissions are set to reat/write on the mbox file

if i change the properties of the file to view it with Text Edit, I can see all the characters of text so I know there is information there

The file size if 663 kb

The file extension is .mbox

I'm not an IT person - just a very frustrated small business owner (completely frustrated)

Is there anyone who can give me a straightforward answer to make this work.  The software is still under warranty but I've given up trying to get help from Microsoft Support.