DC Reader is the Microsoft Vista of document readers
If you have the "new" DC Reader...get rid of it.
The phrase "Not Responding" shows up more than a taxi in New York City.
This has got to be the crappiest Adobe product I've ever had the displeasure of working with.
I've told my company's IT department to start looking for something else.
Acrobat Reader DC is pure American ****.
I suggest you update your Reader to the latest version and if you still face any issues please elaborated them and allow us to help you.