Photo Viewer is a free image viewing utility that enhances your photos to level up your viewing experience.
Some users notice this photo app opens photos very slowly compared to classic photo viewer.
The only problem with the Photos app is that its a bit slower than the classic Windows Photo Viewer.
Microsoft has hidden Windows photo viewer for Windows 10 systems.
Simply open up configs and go to System > Default apps.
Under Photo viewer, you should see your current default photo viewer (probably the new Photos app).
Click this to see a list of options for a new default photo viewer.
Save the file with any name with the extension .reg file.
initiate the registry file and let it add entries to the Windows registry.
Save it as any name with .reg and spin up the registry to make changes.
On the right side, scroll down to see the Photo Viewer section.
You have enabled and set the classic Windows Photo Viewer as the default photo viewer in Windows 10.