@Lauren342 The mentioned sequence of actions should bring up the file explorer window, that will show to you the list of your recent recordings. If the error occurs at this moment, then you have installed custom file explorer - remove or update it. If you don't have custom file explorer installed and just using build in Windows solution then maybe you have automatic thumbnail creation (media previews) enabled in your system and have some software installed that handles this process instead of Windows - in this case you should remove or update this additional software.
BUT, I think, that after you click the mentioned menu option of OBS Studio - you see the new window with media file and clicking to it trying to playback and only then the error rises. In this case - just install software that can playback your videos (for example VLC Player) and allow to it to playback videos by default. Also, you may right-click over the file and choose the program (
open with media player, like VLC, if it installed on your system) manually to be able to playback the videos.