Fix slow thumbnails on a Windows PC

By@MisterFoxOnline

Oct 12, 2025 #performance, #thumbnails, #Windows Explorer, #Windows settings

My dev box seemed to be battling to display thumbnails when I browsed my photo folders. It is a PC with 32 GB of RAM, and the Task Manager was showing plenty of spare memory.

In this tutorial:

Problem
Solution

Required knowledge:

Windows File Explorer

Problem

Slow-loading thumbnails in Windows Explorer.

When a folder of photos is selected in Windows File Explorer
With the View set to Large icons (or Extra large icons)
The thumbnails do not display (or take a long time to appear)

Solution

Customizing the properties of a Windows folder.
Optimizing a Windows folder for pictures.

Right-click the folder & select Properties
Select the Customize tab
Set Optimize this folder for:
To Pictures
Select the Also apply this template to all subfolders option
Click Apply
Click OK

Mister Fox AKA @MisterFoxOnline is an ICT, IT and CAT Teacher and Young Engineers instructor. He has a passion for technology and loves to find solutions to problems using the skills he has learned in the course of his IT career.