My HP 27es 27-Inch is flashing red, green, blue, black, and white. Locked out of OSD

[calebluebbering]

My friend asked me to try and fix his monitor. It is always flashing these colors no matter what. Even just the power chord plugged into the monitor (no HDMI or other output) and it still flashes these colors. The OSD is not what it used to be according to him, and is now a small black box with minimal text. New OSD  <--(Link to what it now looks like) 

It seems to have locked me out. I looked up many things and tried those, but nothing helped. I tried holding down each button and different combinations of buttons but nothing did anything. I have no idea what to do and the people my friend got it from said it would cost money to fix, which he doesn't want to do since it isn't his fault.

In the video, you can also see it says "Key Pass" and "Key Pressed when certain buttons are pressed.

[Prométhée]

Sorry, it's not clear
"and the people my friend got it from said it would cost money to fix, which he doesn't want to do since"

He bought it or the screen, is it not guaranteed?

[calebluebbering]

I am not exactly sure what you are asking, but my friend bought the monitor from Best Buy about 3 years ago. Getting that fixed would cost money which he said he doesn't really want to do, so I am wanting to fix the monitor on my own.

[Prométhée]

I just asked if he was still under warranty

so obviously no
now you don't seem able to fix this screen ..
You would need tools, means to identify the failure, because it can have several causes in my opinion
The best he can do is find a specialist repairer and ask for a repair quote.
It may be more beneficial to replace it depending on the cost!