This one is fun:

One day, your thumbnail preview icons turn into black squares instead of showing a preview of the file’s contents as usual.

You may even find that the usual methods to fix the problem simply don’t work.

Fear not! With a few easy tricks, you can get your black icons displaying previews again…

And you just might discover something new along the way!

Off we go:

So there you have it. The solution may not be what you expected, but it will work.

And you just might find yourself being even more productive than before!