My Windows Defender is Turned Off And Nothing I do Will Turn It On. Do I Need To Re-Install?

1. Open an elevated command prompt. To do this, click Start, click All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator. If you are prompted for an administrator password or for a confirmation, type the password, or click Allow. 2. Type the following command, and then press ENTER: sfc /scannow The sfc /scannow command scans all protected system files and replaces incorrect versions with correct Microsoft versions.

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