Could you please let me know the exact version of Lightroom installed on your computer?
Also are you importing the images from any external drive, or from internal drive of the computer?
I am importing from my external hard drive where i saved all the photos in a file , I'm using lightroom from the creative cloud
Do you get an error message displayed if so post a screen capture or quote the message exactly as displayed.
Please check and make sure that you have Lightroom 2015.7 installed on your computer.
Also try unchecking the option for "use graphics processor" from preferences>performance.