Adobe Digital edition (4.5.10 and 4.5.11) hangs when opening e-book (File extension EPUB)

Hello Team,

I am new to Adobe Digital Edition. Recently installed version 4.5.10 in my Dell Laptop (Lattitude E5470, Windows 10, 64 bit), and whenever, I try to open the e-book File extension 'EPUB'), the application hangs and throws message in few seconds as 'Not Responding'. I don't have any option other than closing the application. I was asked to get an id from adobe site and authorise using the ID, which I did(used my office mail id), still problem persisting for both 4.5.10 as well as 4.5.11. 

I also tried uninstalling, restarting and reinstalling - nothing is helping. would appreciate if any one can help me to fix this issue. It is bit urgent please.