Had the same problem on my S4.
I fixed it by pressing and holding the 'home' button, which brings up the 'task manager' screen.
On the menu bar at the bottom, press the left hand button, don't know what it's called (it looks like an unevenly sliced pie).
This will bring up a menu bar at the top, where you'll press the "clear default" button. Then you'll see a list of apps with "clear" buttons next to them.
I pressed "clear" for everything, to make a clean start again.
When you go back to your emails and press a link someone sent you it will ask "complete action using..." again. Select your choice and it will not ask you again for this type of link.
Do the same for photos sent in Whatsapp etc.
Hope this helps, was tearing my hair out over this.