Hello,
Welcome to Microsoft Community forum. Let's see what we can do about your duplicate photos in Photo Gallery. It is possible that there are really two copies of the photos on your computer. Photo Gallery doesn't actually store the photos, but views them based on what folders are included.
To verify this right-click a blank part on the Photo Gallery (where the photos are shown), then select Group by, then click Folder. This will sort the photos based on the folders where they are located. Then, check if there are duplicated photos located on other folders.
From there, you can opt to delete the duplicated photos located on the other folder. You can also try to remove the folder from Photo Gallery by following these steps:
- Click File (Or press Alt+F), then click Include folder.
- Select the folder, then click Remove.
If in case the folder is not shown, the folder is under a selected folder (like My Pictures). You may need to move the folder to a different location or delete it to prevent it from showing as a duplicate in Photo Gallery.
Let us know how things turn out!
Thank you!