Everytime during starting laptop I see BSOD with error message "SYSTEM_SERVICE_EXCEPTION (cng.sys)". It does not happen during reboot.
The advice that helped me http://www.tenforums.com/bsod-crashes-debugging/10555-bsod-system_service_exception-cng-sys-when-turning-laptop-3.html#post462877
Go to Control Panel-->Power Options-->Choose what the power buttons do click the words that say "change settings that are currently unavailable" and lastly uncheck the box that says "Turn on fast startup"
Ironically by turning off fast startup I've significantly decreased the duration of startup time.
When you are working and then your display screen is appearing blue then it may be the issue of bluescreen error is occured. It can be solve when you will update your files.