For several weeks now I have been getting blue screen warnings with an audio message encoraging me to phone a Toll-free Help line (1-844-552-7825) in order to fix it. If you have this problem DO NOT call the number as it is a complete scam. You will get an Indian voice claiming to be a Microsoft Technician and may end up being scammed for a couple of hundred dollars. Here's how I eventually fixed mine, all thanks to a bright gentleman called Stelian Pilici .
I found the fix at the malwaretips.com webpage. There are 4 distinct steps - don't be satisfied with just the one step and believe that the malware has been removed - be patient and take the time to go through all 4 steps.
STEP 1: Remove Windows Warning Error adware with AdwCleaner
STEP 2: Remove Windows Warning Error browse hijacker Junkware Removal Tool
STEP 3: Remove Windows Warning Error pop-up virus with Malwarebytes Anti-Malware Free
STEP 4: Double-check for the “Windows Warning Error” malware with HitmanPro
In each case you will be able to download an executable file that you should run. Step 4 will prompt you for a product code after you have completed the scan. If you don't wish to purchase a license, opt for the free 30-day trial - this will activate the part of the program that carries out the cleaning of what malware remains on your computer.
There is also an optional 5th step you can take if you need to - you'll find that on the malwaretips.com webpage. Please note that I cannot guarantee that this will eliminate your problem as scam artists are forever changing their methods, software etc.
I hope you have found this useful - if you have please share it wherever.