Help! all of a sudden my screen is to large and can't see error messages of right hand scroll. How do I make it smaller?

[jeffmcpa2010]

Hold down control key and spin mouse wheel.

[Old_Hat]

 tried that and it works to increase/decrease the print size but not the whole screen. I still cant decrease the size of the whole screen so that I can scroll from the right side and see error messages. What did I do?