A user states that after changing his display settings and rebooting he cannot see ?

A user states that after changing his display settings and rebooting he cannot see anything! The icons are too distorted. How to resolve this issue and get the icons back to normal size?A user states that after changing his display settings and rebooting he cannot see ?
reboot pc once the pc starts to reboot, start to hit continuously the F8 key on the very top of your keyboard then you will see a menu, go to Safe mode and it will ask if you are sure you want to go to safe mode say yes then you will be in safe mode which will show your icons very large then what you can do is on an empty spot of your desk top do a right mouse click and go to properties then go to settings and there you will see the screen resolution move it back to a lower resolution apply and ok the pc will reboot back to normal windows and problem solved.A user states that after changing his display settings and rebooting he cannot see ?
User needs to make sure that a monitor he/she uses supports that certain settings (Screen resolution, color settings, refresh rate...).

Another way is to connect other monitor on his/hers computer and to see what happens.