I am running Adobe Acrobat XI 11.0.13. More often than not, when I open a pdf it will cause the program to freeze up and not respond. I am running windows 8.1. I have checked the event logs and all I see are Application Hang errors with the event ID 1002 error telling me that Acrobat.exe has stopped interacting with Windows and was closed. To see if more information about the problem is available, check Action Center control panel.