MacBook/VGA hookup Q. Need answer fast!

Tech question for Mac people: My MacBook Pro just stopped synching with the VGA hookup for my school projector. I have the cable adapter and it normally works. Is there a quick fix for this? Like pushing COMMAND and one of the F buttons together or something? Have tried rebooting, reconnecting, resizing in VGA mode, repeatedly. What am I missing? I get the screen saver on the projector, a skewed view of the icons, and none of the PowerPoint I am trying to show my students.

Go to System Preferences->Displays and play around with the available resolutions until you find one that works.

I tried every one they offer, none works. This worked fine until yesterday.

Your adapter is probably broken (the H or V sync wire is broken) - try moving the cord around and see if it starts to work.

Sounds about right. Thanks!

Probably not this, but make sure that in System Preferences–> Displays you have Mirroring turned on if you want your laptop screen to be what is on the display.

Sounds like it is probably a wonky dongle, though.