Computer sceen first doesn’t work then it does after you connected another screen before it.

[Fulbert]

We have done some remodelling in store and we have this screen that is connected to a computer. But I refused to turn on. We have check all the cables and everything is in order. 

The only way for it to start, is if we first plug in another screen and then when that one starts with the computer, switch the cables so the actually screen is connected. Then it usually works. What do we do? 

[Lil_Boy_Blue]

Hi

I dont really know.
AND/OR - Windows Logo key + Ctrl + Shift + B
(This key sequence actually restarts you graphics driver (W10 only).)

AND/OR - If you’re using multiple displays, try projecting video to a different monitor.
Press the Windows Logo key + P, select a display, and then press Enter.

[Fulbert]

Am I supposed to do that when the screen is working (after connecting in another and then back to the correct one) or when it is in the state of not working? 

[Fulbert]

I can upload a film on how it is, if that is possible. I’m not that good friend with technical stuffs so all help is appreciated. 

[Lil_Boy_Blue]

Well if it boots and no screen display, then try those key combinations.

But I still maintain I don't really know.