Acrobat not starting

 "Adobe Acrobat has recovered one or more documents that were not saved properly before Acrobat was shut down. Click Yes to open the recovered documents. If you click No, your changes will be lost." is the message I get every time I start the application. Clicking either Yes or No results in the the app going dark and I have to open Task Manager to End Task to close the app to continue.

What should I do?

Steve