Can't change Screen Resolution on External Monitor

Hello Dear Community,
I have fixed my laptop in the other discussion (my 4 days old laptop... Wont turn on!!)
And i connected it to an external monitor, because the laptop itself has a broken display.
Now, the Resolution of the screen on the external monitor is too high. Everything is way too big. And it won't let me change it, no matter what I do. I even updated all the graphic drives (or whatever they are called) but it still doesn't work.
Any solutions?
I would be happy to use my "laptop" normally, at least until I buy a new display and let an expert switch the display.

Accepted answers

Sergejalex

Nevermind, Ive found the solution.
My laptop was thinking that it is connected to an external monitor, and it didnt work. I have to detach the HDMI cable, power on the laptop, and THEN put the HDMI cable in. Thats how ive fixed it. Thank you for your help, anyways!

All comments

ijw

I think you are using Windows 10

By default, Windows 10 will chose the best display settings for your computer based on the monitor and video drivers installed. You can change the screen resolution manually for each monitor that is connected to your computer.

Right-click an empty area on your desktop, and click Display Settings.
Click on Display on the left pane.
In the right pane, scroll down and click on Advanced display settings link.
If you have more than one monitor connected to your computer, then select the monitor that you want to change the screen resolution of.
In the Resolution drop-down menu, select a screen resolution (ex: 1920 x 1080) that you want for the selected monitor.
Click Apply.
If the selected screen resolution mode is optimal, click Keep Changes (Figure 1).
If you have more than one monitor connected to your computer and would like to change the screen resolution of another monitor, then repeat Steps 4 - 7.

Sergejalex

@ijw, yes I am using Windows 10. I forgot to tell you that the Screen Resolution option is grayed Out. I cant press it.
And yesterday, I accidentally changed the screen SCALING to 500% and then, everything was Huge. I couldn't revert it, so I just turned off my laptop, and now, it doesn't show any screen at all! No screen on both screens, external and normal. I don't understand. I even used Narrator and navigated myself blindly to the Scaling setting. I tiped 100% and Apply, but it doesn't work. I don't even think it is on 100%... Do you have any solution? I just want it to work..
And: it's black screen before the booting and windows logo. There is no screen at all.. But I can clearly hear the Narrator and use Cortana.. What shall I do?

billsey

Try hitting Windows-P and using the cursor to select each of the modes until the display shows up again. Windows-P is the Projector mode select, giving you the options of only displaying on the laptop screen, mirroring the laptop screen on an external, extending your screen to the external, and using only the external. You want the last one. I'm betting you were on mirror, which forces the external screen to match the resolution of the internal.

Sergejalex

@billsey, ok, Ill try it, but I cant see anything. And It doesnt work on an other laptop, too. But the Hdmi cable works, because the Nintendo Switch works perfectly on that monitor. But Ill try it again now.

Sergejalex

@billsey, I cant see if I am pressing sonething. I tried Windows+ P, and then clicking down and enter, but nothing happens..
Is there any command I could write in The "Run-App"?

Sergejalex

Nevermind, Ive found the solution.
My laptop was thinking that it is connected to an external monitor, and it didnt work. I have to detach the HDMI cable, power on the laptop, and THEN put the HDMI cable in. Thats how ive fixed it. Thank you for your help, anyways!