Display size problems with two monitors I just added a second monitor and my display is mis-sized. My macbook air monitor extends partly onto my external monitor. There are parts of the display that are off-screen - if I move my mouse to each side, the display will shift slightly with it, like the display is too big to fit the monitors. I've tweaked with the display resolution to no avail. Any ideas?



There's a black box in the bottom right corner where the mouse won't go, so the actual image is a bit taller than this. Also note how the left side of the window gets cut off.



I am running Snow Leopard; pretty sure zoom is not the issue.
That's what it looks like and that's the behavior when you zoom in on the laptop screen.  You can zoom in (even under Snow Leopard) via the trackpad or scroll wheel or keyboard.  In Snow Leopard there settings for screen zoom in System Preferences under "Universal Access" (both "Zoom" and "Zoom Options..."), "Mouse", and "Trackpad".  See what you have configured and use that to unzoom the screen.

I think the default zoom is ⌘+scroll wheel.

You have been able to zoom in on the screen as part of Universal Access for as long as I can remember.  You still can in Lion.