Circumflex keys problem

Hello,
I am asking this question because I did not find the same topic on other forums. I can not write E with circumflex accent above but yet the key functions: ^ ^ ^
nor any letter with that accent.
I have also changed the keyboard but nothing works.
anyone know the origin of the problem?
Thank you and good day

The circumflex represents the Control (ctrl) key. In System Preferences Keyboard Shortcuts it has an item ticked that says SHIFT CTRL CMD 3 will copy a picture of the whole screen to the clipboard. When you perform this action nothing is placed in the clipboard at all. In other words it doesn't work. So are you certain that ^ means CTRL?

The inconsistency is a little frustrating to say the least. There would be nothing to stop the CTRL key having a ^ on it, after all the rest of the odd keys ALT CMD etc have strange icons signs on them why not the CTRL so we'll know it's called ^ ?
If you would be kind enough to elaborate on this and give me a clue as to why it doesn't work when using the Ctrl key combination they say should work. The shortcut is enabled by the way.

You can change the language of your keyboard. I like to work in the Catalan or the Spanish keyboard (depending on which computer I am using). Then I find a circumflex by hitting the key to the right of the P, and holding down the capital key at the same time. That gives me a circumflex, which remains invisible until I hit a vowel, which produces the vowel with a circumflex. â ô If I want the circumflex alone, then I hit the forementioned circumflex key and hit the space bar. ^
Edit: First, you need to go to your Windows setup, and find the keyboard countries. You pick out Spanish, or Catalan, and thus you will add it to your desk top (the language bar will appear in your blue line at the bottom of your desk top). You will see EN for English. click it with your mouse and your different choices will appear. (I can choose Spanish, French, Catalan, English). French also has the circumflex.

This problem also exists for German keyboards and it seems to be well known since many years. It even exists in .NET Framework 3.5 SP1.
The only work-around I'm aware of is the following:

using IWshRuntimeLibrary; //reference 'Windows Script Host Object Model' from the 'COM' tab

WshShellClass wsh = new WshShellClass();
object wait = false;
wsh.SendKeys("{^}", ref wait);