Microsoft word crashes randomly when I try to add citation via endnote.

Hello!

I recently started using Endnote. 

This is just the first real paper I am working on with Endnote; and its already giving me a lot of trouble. My microsoft word (which otherwise works rather well) seems to crash for no reason at all when I try to attach certain documents to it. 

Please help me find  solution to this problem. 

I need it fast. I have a deadline on this paper and I would really like to use both Microsoft Word and endnote. 

Thank you