I have a client who sends me emails with a jpg signature attached and it's actually a small file but when I hit reply on theirs or any other email that I have not opened yet then I get about a 5 second "not responding" pause before it eventually normalizes and I can work.

I think that the problem is whatever program previews the jpg inside the Outlook 2016 Windows 10 64bit application.

Has anyone experienced this or have any idea how to solve?