I had a weird thing happen to me today. I needed to download a copy of a video I posted to Facebook. That video should have downloaded as an MP4 file. However, the file kept downloading as a .jpg file. A .jpg is a still image.

Stranger still, when I tried to open that .jpg file, I got a warning that it wasn’t an image file at all. It didn’t matter which browser I used or even if I switched computers.

I fixed the issue by changing the file extension. I knew the file was indeed an MP4, so I thought it was worth a try. To do this, you’ll need to be able to see the file extension. So, click the View tab in File Explorer.

Then tick the box next to View File Extensions.

Then right-click on the file you want to change the extension for and choose Rename.

I’m selecting the .jpg…

…and replacing with .mp4.

There’s a warning that changing an extension can mess up a file. I hit Yes, anyway.

And suddenly, the appropriate file appeared. I had an MP4 that was ready to play. I’m not sure what caused this mix-up in the first place, but I am happy I was able to fix it.