Keyboard Layout changes.

Win key + space shows you immediately which keyboards you have available and toggles between them.
ALT + Win toggles immediately.

You may be tripping over the 2nd of these e.g.

You can remove the offending keyboard if present, or if it's a hotkey combination giving you trouble there are ways to nullify that.

More:
Are the @ & ” Keys Swapped On Windows 10? – How To Fix It

If this is what you have done then the problem will not happen again without your knowledge
- the WinKey+Space combination flashes a dialog onscreen to warn you that you have been toggled but it cannot be disabled

Settings,
Devices,
Typing,
Advanced keyboard settings,
Input language hot keys,
Advanced key settings tab,
Change key sequence,
Set Switch input language to Not assigned,
Set Switch keyboard language to Not assigned,
OK,
OK.

Denis

dalchina said:

You can remove the offending keyboard

We no longer seem to have a method of deleting an unwanted keyboard.

I've had a US one added [presumably by a Version update] and I cannot get rid of it.

Denis

Perhaps lx07's approach (post #1) provides a solution where it's the original default layout:

Add or Remove Keyboard Layouts in Windows 10

dalchina said:

Perhaps lx07's approach (post #1) provides a solution where it's the original default layout:

Add or Remove Keyboard Layouts in Windows 10

No, there's no mention of US on the Settings, Time, Language dialog. It only exists as the keyboard that is toggled to by WinKey+Space.

We used to be able to delete keyboard layouts. I don't know when that changed.

Denis

The tutorial makes no exception by build number.

dalchina,

Perhaps we are talking at cross purposes.

My Settings, Time & language, Language dialog has no reference to any US layout/language

but the WinKey+Spacebar toggle does switch me to US layout

and I also noticed that US language features are now listed in Settings, Apps, Optional features

even though I have never knowingly added any of them.

---

This has not been a problem for me so far. I only checked the latest situation in order to make sure I was responding accuractely to this OP.

If I ever find that I start accidentally triggering WinKey+Spacebar I will make a new system image then delete those US entries in Settings, Apps, Optional features to see what happens.

Denis