Hi Ken_309,
Thanks for bring up your concern here at Microsoft Community.
It sounds like the functions of the "Next Frame" and "Previous Frame" buttons of Windows Media Player are reversed. There could be something wrong within the app.
Try to reinstall the app to see the effect:
- Open Control Panel > Programs and Features > Select and right click Windows Media Player > Click Uninstall.
- Download the latest version of Windows Media Player from Microsoft Store and then install it to your Windows.
Feel free to post back if you need further assistance.
Best Regards,
Lynn Sun | Microsoft Community Support Specialist
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