How do I disable dual monitors?

Go to System Preferences -> Displays -> Detect Displays. It should realise there is only one display connected

uumm havent u restarted ur mac in that time?? i thout it detected the monitors every time u restarted. strange.. hope its ok now

mothra1961 said:

Scarlet, I don't have an option called Detect Displays. When I go to System Preferences -> Displays the three options I have are: Display, Arrangement, and Color. If I select 'Display' the options are: Colors, Refresh Rate, Gather Windows, and Show Displays in Menu Bar.

Also, I have restarted many times since I disconnected my second monitor and my situation hasn't changed. This problem is more of a nuisance than anything else, but it would be nice to solve it...

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It's in the arrangement tab that you'll find "detect displays". I think that should sort it out.

Same problem here

I have the same problem as mothra1961 has (or had).
I cannot find a working way to disable that other monitor. I tried pressing the "detect displays" button several times. Not working. I connected and disconnected other display in the mean time. My MacBook still thinks the old CRT Monitor is connected when it's not. (Another annoying thing about it is that the extended desktop holds files i cannot access, since my monitor is not attached.)

Lately, I upgraded to OS 10.5 Leopard (after having formatted the system volume) assuming that the problem might be solved afterwards. However, it's still there and system profiler even states "yes" next to the monitor's online status. I wish i could simply tick "no" right there...

Now, I wonder if my hardware is somehow damaged or if a simple click in some application or preferences pane could make the system ignore that darn display.

Any ideas how to work this out? Or, mothra1961, have you fixed your issue and could you tell me out here?

Mavericks and Yosemite need the Option key down to see "Detect Displays"

http://osxdaily.com/2014/03/31/detect-displays-mac-os-x/

junglecode said:

Mavericks and Yosemite need the Option key down to see "Detect Displays"

http://osxdaily.com/2014/03/31/detect-displays-mac-os-x/

Click to expand...

Well, that probably was not an issue for the posters from 2007....

A.

Alrescha said:

Well, that probably was not an issue for the posters from 2007....

A.

Addendum: no harm done, we have all done it at least once.

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I posted because I found/fixed the same issue today on Yosemite. Helping out the next poor sap who stumbles on the original post from a web search (like I did.)