I took a computer programming course and was pretty savvy with troubleshooting. However, that high school course was a couple of years ago, and you might not be on an Apple 2E, so I am not sure the advice would be helpful. If your screen colors inverted and the background is now green (or orange) and your text is now black and you want to switch back to black background and green (or orange) text, or if you are having problems with Oregon Trail -- let me know and I might be able to help.