After checking out some results of a search for solutions to the problem in the subject of this post, I realized that I’m not going to find an answer that way. What’s happening is too weird.
I’ve had a second language (herein referred to as Lang. 2) installed in various versions of Windows for many years, incl. Windows 11 for the last 8 months. My marvelous keyboard, which came with my Blackship 486/25 back in 1991, doesn’t have a Windows key (that key didn’t exist yet). I can switch to Lang. 2 using Alt-Shift, but I normally just click on the language indicator in the system tray area. Today, when I clicked on the icon and then on Lang. 2, the indicator changed to Lang. 2, but my typing produced English letters.
Here’s the weird symptom. I checked all the Lang. 2 letters and two of them displayed as the correct Lang. 2 characters. The rest all showed as English.
I tried uninstalling the Lang. 2 pack and reinstalling it.
I rebooted.
And although I knew it wouldn’t help, I plugged the keyboard into a different USB port. (Yes, I know that there was no USB in 1991. When the serial connector – or more likely, the port – stopped working, I bought a serial to USB adapter.)