How to change monitor assignment in a dual monitor environment

Found the resolution to this issue.

1. Leave the screen resolution screen up on the monitor you want listed as 1
2. Unplug all of your hdmi/dvi or other visual cables from the monitors or computers (whatever is easiest for you), excluding the one you want listed as display 1.
3. if you only have one monitor plugged in and still see a monitor listed in the display screen settings window, hit the detect button to flush it out.
4. From there, start connecting them as you'd like in order from 2 to #X.
5. Once done hit the apply button.
6. Previous to hitting the apply button my monitor 2 (right of my monitor 1) would require me to slide my boxes to the left of monitor 1.

I just had this issue after making a few changes

Steps 1-3 worked as normal, but step 4-6 didn't work for me (I have Win 7 home premium, Service pack 1).

The left monitor was assigned #1, the right was assigned #2.  I unplugged the cable for the left monitor and then the right monitor became #1 and everything (icons, taskbar, etc.) moved over to the right monitor as expected. I hit detect and identify and "1" showed on my right monitor as expected. I had to change from landscape to portrait to fit the orientation of my right monitor.

But when I plugged in the cable for my left monitor, everything went right back to the way it was before.  I mean literally everything - not just the left monitor being assigned #1 and being in landscape mode but every single icon went back to it's original position (I have about 200 icons semi-organized on the left monitor and 6 icons on the right monitor). This seems more than just a registry setting mentioned by someone previously.

I'd say Microsoft has been good at ignoring this particular problem but the icons going back to the way they were is new to me. A few years ago if the monitors went back to the previous number assignment all the icons would remain a jumbled mess in the old #1 monitor.  That was the main reason why I used the adapter trick for my KVM switch (and why so many people wanted to disable the auto-detect pin when using KVM switches). Before the adapter trick every time I used the KVM switch the icons would shift to the second monitor when it became #1 and then stay there when it became #2 again. 

4 years and counting and we're still waiting for a someone to verify a workaround. I'd assume someone new would try everything mentioned above from least effort to most effort and maybe something will work.  I'd say the adapter trick is the most effort (it's fairly easy though and costs about $7) but unless Microsoft sprinkled some new magic on Windows it's the one that works.

The auto-detect pin being disabled on a newly connected monitor prevents the #1 assignment from being reassigned to that new monitor which is the solution. If you have any doubts just search the web for  autodetect, pin, kvm.

Go back and read the Mathew Wagner comment.

My guess is that to reassign the monitor numbers, you must unplug the secondary monitor, after, if you extend,  carefully moving back all the programs that you've closed in the secondary extension.

I found the way to fix the numbering.  Disconnect the second monitor and go to the display setting screen.  Click on "Identify".  When I did this the number assignment of my main laptop monitor changed to "1".  Then when I connected my other monitor it took the number "2" slot.

Hope this helps.

You can’t change the primary number but id solve the problem in which start up display priority in booting up on windows

Go to "bios" - "init display first"

just select priority display that fits on your Pc.

Pci slot -

Onboard -

Peg -

Just be careful!

For me i used Peg

My video card has 2 ports "VGA" primary monitor but #2 in display and "DVI" secondary monitor but #1 in display.

Hope it helps.