MacBook Air 2013 operating system issue. This video will show you how to install a clean image of macOS Mojave. This MacBook Air is giving a blinking question mark within a folder icon when booted. 

This is how to perform a post test on new PC components. This video will give you an idea of how to install you components and what to look for. 

Some windows 10 PCs are not receiving the new May 2020 update automatically yet. If you're impatient, here is how to manually download and install the update.