In Windows 10, how can I enlarge thumbnail size?

Even after selecting Extra large icons, the thumbnails are too small for me to discern the images. I completed the steps for:

1. Option 1: 'To Turn On Thumbnail Previews in File Explorer'.

2. Changing Image Thumbnail Size per this Registry Hack Method.

But my thumbnails have not enlarged.

2 Answers

I recently got a new laptop with (Windows 10 and 4K Resolution.)
Changing the thumbnail size to Extra Large increases the spacing, but doesn't make them any larger & the Registry Hack didn't seem do do anything!

-The only way I found to make them larger, was to change my screen's Resolution to a lower setting.
Although it makes everything else larger as well, which could be annoying to some people.

The way I do it is to hold ctrl and scroll the mouse wheel up while in the folder.

Another way to do this is to go to:

Windows Explorer -> View tab -> Large/Extra Large Icons (Under Layout section).

This transforms my view from this to this.