Hi
Welcome to the Microsoft community.
Cool File Viewer is not a Microsoft product, so if you could, I suggest you reinstall it to see if the problem still exists? If the problem still exists, you can try to replace a file browser to exclude the problem caused by the Cool File Viewer itself.
You are welcome to reply to this topic, and I sincerely thank you for your support of Microsoft products and services.
Best regards
Derrick Qian | Microsoft Community Support Specialist
* If your problem is not solved, you could reply to the post again and we would continue to provide technical support for you.
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