Send To Mail Recipient Issues

At some point in the last couple of weeks the Send To/Mail Recipient function has stopped working. When I select a file and do the send to, Windows starts thinking, the explorer window that I have selected this from stops taking input and then eventually, with no error messages, the explorer window closes and desktop explorer resets.

My Default mail client is Outlook 2013 (15.0.4745.1000)

Thanks in advance for any suggestions!

I have the standard Windows10 and Outlook2013. I don't normally send files so I selected one, a photo, and clicked on "send to mail recipient." After verifying the size of the photo a email window opened and was just waiting for an address. All seemed to function as intended.