Mac thinks external Dell display is a built-in display So I have a Macbook Pro running OS 10.11 with 1 additional Dell display. For Christmas I received another Dell display, but I'm having issues with this mac thinking the new display is a "Built-in" display. When I bring up the Display Preference, it shows my old Dell display as a DELL E2414H, but the new Dell display is showing up as Built-in display. Both displays are exactly the same, with the only difference being how they are connected. The older display is connected via the display port adaptor which is connecting via VGA, while the new display is connected to a USB 2.0 adapter also connected via VGA. Since the new display is being recognized as a built-in display, the resolution is all fuzzy and the task bar is outside of the screen. When I look at the resolution settings and view the scaled options, everything is set to 1920x1080 ( as it should be).

When I open up the About this Mac menu, it shows that I have 2 additional displays, but says the new one is 30.5 inches ( It is actually 24 inches, just like the other display). I'm assuming that since the Macbook thinks the display is much larger than what it is, this is what is causing the bad resolution. Is there any way to fix this? How do I forced the Macbook to recognize the display for what it really is?
There may not be drivers for this monitor set up for the MacBook. Check if you can find drivers online for this monitor.