HDMI TV becomes primary monitor when plugged in.

Hello,
I have been searching all over for the following problem:

I have a normal dekstop-pc setup with a 24" monitor hooked up to the graphics card with a DVI cable.

To be able to watch a movie on a bigger screen, I hooked up a standard 40" TV to the graphics card via the HDMI cable.

I then Duplicate the screen and play the movie on the PC (they are in the same room). When I do other work on the PC, I turn the TV off.

For me this works fine, the problem however is this:
Windows 10 now sees the HDMI-TV as the FIRST monitor, and my desktop as the SECOND.
(I didnt realize this for a long time until I played a game recently and the screen kept flashing and I was having all kinds of problems where the game just wouldnt run right, which was solved when I pulled out the HDMI cable.)

So, how can I tell Windows to set my Desktop monitor as the Primary and the TV as the secondary, and leave it that way without having to switch settings when gaming or watching a movie.

Thanks for your help,

Well that works, got it figured out. Thanks!