Please go to Edit>>Preference>>Performance>>Uncheck "Use Graphics Processor".
Restart Lightroom and re-import images from a different source.
Let us know if that helps.
I did mention in my post I have tried the suggestion posted in the forum which included the above and as of now it is still unchecked. it has been for over a week and did not help at all.
I am not sure what you mean by re-import images from a different source and how that would help me with importing the CR2 images from the memory card of the camera. That is a basic function of the programme and creating the pre-views.
Does the problem stops responding even when you import few images from your desktop?
There might be an Read/Write issue copying from Memory card.
Also have you optimized your Lightroom catalog from File>>Optimize catalog?
Importing a few images or hundreds does not stop the programme but when the previews are created it stops responding. It is the preview creation after import that stops the programme not the import.
Yes, the catalogue has been optimized, too.
Let me put it this way.... I have Lightroom 5.7.1 on the same PC and I do not have any issues with it. It does what I want it to do unlike the 6.5 version using the same memory card and same CR2 files. But since you decided to stop updating camera raw files for the new release cameras of the V5.7.1 I had no option but to upgrade to a version that does not work properly. When someone purchases a software it is expected to work properly without sending the user around the bend. The 5.7.1 did just that, worked. The 6.5 have never worked properly.