Hi Raphaela. I'm Greg, an installation specialist, 10 years awarded Windows MVP, and Volunteer Moderator, here to help you.
- I don't see any mention of the Night Light which gives the screen a yellowish-orange tint to be easier on the eyes at night. Check in Settings > System > Display > Night Light if turning it off resolves this.
- The Display driver is so important here that merely updating it is sometimes not enough. So let's try everything possible to get it working correctly:
First make sure you have updated the Display driver from the PC or Display adapter maker's Support Downloads web page for your exact model number, HP Serial Number or Dell Service Tag - from the sticker on the PC.
If necessary first remove the old driver using DDU (not necessary with Microsoft Basic driver which is a placeholder if nothing else is available) and/or installing in Safe Mode with Networking (so you have internet), or Safe Mode, accessed by one of these methods: https://www.digitalcitizen.life/4-ways-boot-saf...
While there check also for newer chipset, BIOS/UEFI firmware (very important), network, sound, USB3 and other drivers, comparing to the ones presently installed in Device Manager reached by right clicking the Start Menu.
If this doesn't give you the latest or ideal driver for what you need, compare it to the driver offered by the Intel driver update Utility here: http://www.intel.com/content/www/us/en/support/...
or the Nvidia Update utility here: http://www.nvidia.com/Download/Scan.aspx?lang=e...
or the AMD autodect utility here: http://support.amd.com/us/gpudownload/windows/P...
For Display issues one fix that is working is to Roll back or Uninstall the Driver on the Display Device > Driver tab, restart PC to reinstall driver.
You can also try older drivers in Device Manager > Display device > Driver tab > Update Driver > Browse > Let Me Pick.
Then you will know you've tried everything in addition to Windows Update drivers.
Adjust the screen resolution until it fits and looks best at Settings > System > Display.
- Reset the theme by setting a new Theme from Settings > Personalization > Themes or from the many spectacular free Themes you can download from the Store to that control panel to choose from: https://www.microsoft.com/en-us/store/collectio...
If you don't want the theme used to reset this, you can then personalize with your own background slideshow or picture in Settings > Personalization > Backgrounds, but most personal pictures are not as high resolution as the Theme packages which are some of the most expensive scenic pictures ever taken. Here's how to change backgrounds: https://www.laptopmag.com/articles/change-deskt...
and here's how to Troubleshoot Backgrounds not working:
https://windowsreport.com/fix-background-slides... (Avoid ad links!)
To get color back on the task bar, start menu and window frames after Version 1903 turned the Light theme dull grey follow this guide:
https://answers.microsoft.com/en-us/windows/for...
To get the spectacular scenic backgrounds back on the Lock screen when the PC first starts up, go into Settings > Personalization > Lock Screen and set the drop down menu to Windows Spotlight.
If you want the Fun Facts you can hover the mouse over on the Lock Screen or click to go to info pages about the scenes, change dropdown temporarilty to Picture, tick the box to Get fun facts, then change it back to Windows Spotlight.
More about personalizing by customizing appearance here:
https://www.windowscentral.com/how-customize-lo...
https://www.howtogeek.com/225893/how-to-persona...
To save a Windows 10 custom Theme so you can reapply it when Updates or Version mess it up, see here:
https://www.tenforums.com/tutorials/41564-save-...
- Try the rest of the fixes here:
https://windowsreport.com/windows-10-yellow-tin... (Avoid ad links!)
https://superuser.com/questions/1138070/laptop-...
I hope this helps. Feel free to ask back any questions and keep me posted. If you will wait to choose if I solved your problem, I will keep working with you until it's resolved.
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