Everything seems fine at first, your PC is running normally but then a blue screen suddenly greets you. After restarting your computer you find that a lot of your unsaved work is gone. If this has happened to you before, rest assured, you’re not alone. What you’ve just encountered is the Blue Screen of Death (BSoD) and it appears when there is an issue with either your hardware or software. Fortunately, there are ways to troubleshoot these problems. Here are some of the common causes of a critical failure error and how you can fix them.