By default, Microsoft Office 2016 (and by user choice in Office 2013) blocks all excel files that originate from the internet (generated in the HTML format). MVP's import templates generated by the import wizard use this format. 

Use the following steps to disable the restriction:

1. Click File.
2. Click Options.
3. Click Trust Center on the left.
4. Click Trust Center Settings.
5. On the left, select Protected View.
6. Un-check the first item called "Enable Protected View for files originating from the internet."
7. Select OK to get out of the Settings.