Why can I only print when I try to export?

If you have a printer set up for your machine, it may default to this when you try to export but this can easily be fixed.

Change the output destination

The PDF export routine uses the same browser function that's required for printing, so if you have a printer set up on your machine, it may default to this initially. You should be able to change the destination/output from the printer to PDF - this will vary from browser to browser but using Chrome as an example you can see how to change this below.