Cannot change screen resolution

I'm doing some maintenance work on a friend's computer. I plugged it into my monitor and the screen resolution changed to so low that the whole desktop doesn't even show. It's unusable. I went into safe mode to change the resolution but when I change it and click apply it doesn't save the change, it stays low. I'm at a loss as to how I can get it to change to a usable resolution. Any ideas?

 

What version of Windows is your friend running? Are the appropriate graphics drivers and software installed? Safe Mode only uses the built-in VGA resolution graphics (lowest).

 

I decided to try uninstalling the video driver and let Windows reinstall it and it's better now. Thank you for the reply.

 

Now, when your friend connects his/her monitor to his/her computer will he/she have to do the same thing?

 

I don't know but if so I will do it when I hook her computer back up.