Hi, James McGrory
Welcome to the Microsoft community and thank you for asking your question in the community!
Based on your description, I understand that your monitor screen turned pink after you cleaned the dust and reconnected it.
I think the following troubleshooting options can be tried to attempt to resolve the issue:
It may be that sometimes HDR can cause the monitor to be off-color and off-color, you can right-click >Display Settings>HDR Off, and then check to see if the screen turning purple still exists.
- Replace the monitor connection cable or re-plug and secure the test.
If possible, try to replace a connecting wire and make sure both ends are connected securely, and reboot the machine to test the fault is even troubleshooting? Dust on the interface can also cause display abnormalities.
- Graphics Card Settings Interface Restore Monitor Settings Defaults to Try to Resolve the Problem
This is where you need to find out information about the graphics card your computer is connected to for the monitor port.
- Try updating or reinstalling your graphics card driver to solve the problem.
This requires information about your graphics card to direct you to the official driver download site.
Please let me know if I have misunderstood. Tell us the results and we will get back to you as soon as possible. We look forward to hearing from you.
Best regards,
Yang.Z - MSFT | Microsoft Community Support Specialist