This message will appear when the option 'other users may run this import' has been unchecked, to resolve it:

1.   Open the import causing the message by the person who created it
2.   Go to File, Save As and check the option 'Other users may run this import' and Save
3.   Close the import and the other user can now run it

For more information on this option, please see How to change permissions so that others may or may not run or modify queries, reports, exports, imports, letters and global changes