Windows - Be prepared - PC won't start
You switch on, but Windows does not start. Windows has a built-in tool to create a recovery drive on a USB stick. Depending on what is wrong with your PC, this will enable you to re-instate your PC. You will need a USB drive that's at least 16 gigabytes. Use an empty USB drive because this process will erase any data that's already stored on the drive.
To create the drive is an easy matter: Type recover in to the taskbar search box, then click Recovery drive at the top of the results. The process can take hours.