Forced to close itself

My EndNote library (X8) is continuously forced to close itself after adding or modifying PDF attached to the entry. It happens on both my work (university) and home desk top computers (Window 10). I created a copy of the library and try it - the same problem. It happens to all of my different libraries. Please advise how to fix it.

Please contact Technical Support directly

1-800-336-4474 option 4 then 1