When I turned on my computer screen, a thin red line showed up on the left side of my monitor. I searched what to do, and it wasn't much help. I tried cleanup wizard and display screensaver, but it did not work. I also read that the more you restart your computer, the more lines that'll appear on your screen, but not only will it be just red, it'd be different colors too. I tried doing a spyware and virus scan too. That did not do anything too. Please answer me with a safe and good answer. Thank You! :) I'd like an answer quickly also :)

What kind of monitor is it? LCD or CRT (like a tv)?

Sometimes effects can be caused by overscanning. So it depends on what type you have. Also you should have buttons or switchs you can tweak to enhance the picture directly on the monitor.

I'm not sure if it is an LCD or CRT, sorry. I tried doing the right click, then properties, then sceensaver, then blank, then preview. They said the red line should not appear. It did though. Thanks, I'll get back to you @sap!