The users who experienced this issue reported that some keyboard keys are not working with the Shift key on Windows 11/10. The causes of this issue can be many, like a corrupted keyboard driver, ...

You can turn off Sticky Keys in Windows by pressing the Shift key five times. On Windows 10 and 11, you can also turn Sticky Keys off in Settings and disable the shortcut there. On Windows 7 and 8, ...

For some unknown reasons, secondary shift characters can get activated and display different characters than normally they would. For example, SHIFT + 6 would yield a ?, instead of the ^, and SHIFT + ...