Once Smart App Control has been turned off, it cannot be turned back on without resetting or reinstalling Windows. This is a security feature designed to prevent unauthorized changes to the system. Unfortunately, if you have accidentally switched it off, your only options are to either reset your device or perform a clean installation of Windows to restore Smart App Control functionality.
If you are looking for alternatives or workarounds, you might want to consider reaching out to Microsoft Support for assistance or to explore if there are any updates or patches that might address your situation without a full reinstall.
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