Execute o SFC
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Use the System File Checker tool (SFC.exe) to determine which file is causing the issue, and then replace the file. To do this, follow these steps: 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. 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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Se isso não resolver, você pode estar infectado, consulte este WIKI