ALT and CNTRL keys non-functioning

[Guest]

For some reason, both ALT and the CNTRL keys became non-functional. I
noticed this while trying to use the ALT+TAB toggle function. I also cannot
use ALT to navigate through menus or use CNTRL to highlight multiple items.
Does anyone have any suggestions?

 

[Bob I]

Perhaps you've enabled "Sticky Keys"? Control Panel, Accessibility
Options, Keyboard.