Not really an issue for me cause I can just use 5k player... though I want my libarary to be the only place I need to go.
I have notice that PowerDVD is not reading the codec and I think that is the base of my problem. Is disapointing becuase 5k automatically works and is free.

What settings could be wrong? PowerDVD is the only player I have that cannot read all of my videos(though PowerDVD does play 90% of them). Much thanks for your reply. Full version. Can play h264? I think.

PowerDVD 22. Not sure about patches. All other players will play the videos. Mainly MP4 files it is happening to. If people need more info please ask.

Maybe I just need to reload Videos into libaray?? IDK

Okay so I try something (nothing) I opened one of the videos in PowerDVD through windows (right click, Open with...) and it worked, then I closed it immeaidately and reopened it again in the exact same way and it is back to black screen. Weird? I thinks this shows how small my problem is... lol

Okay very weird! when I simply play any video and just keep hitting next or pervieous till I get to siad video.. ALL videos work as you would expect from PowerDVD. I going to leave this here just incase someone else had this small problem.