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From time to time computers will forget their display settings and/or they may get changed by another user on that particular machine. This can cause issues with how content is displayed across multiple monitors in your office setup or on a classroom projector or television.
As long as all of the cables have remained connected to the same connections and the projector/monitor is set to look for the correct input source, the issue is usually in the display settings of the computer itself.
To change the way your computer is using multiple displays try the following:
For PC
1. Right-click anywhere on your desktop and select Display Settings
2. There is a drop-down menu on the right-hand side. You may see a variety of options, however, you are looking for a setting that says "Duplicate these displays." Click that setting.
3. You will then be prompted to "Keep changes" or "Revert." If everything is correct, then click on "Keep changes."
