Door Mysterio: Please follow these steps, to solve the problem: 1. Deactivate Windows Defender from Start -> Control Panel -> Windows Defender -> Extras -> Options and deactivate the option Automatically scan computer and Use Windows Defender from Administrative tools and click Save 2. Deactivate the User Accounts Control (UAC) from Control Panel -> User Accounts and Family Safety -> User Accounts -> Turn User Account Control on or off Deactivate the checkbox for Use User Account Control (UAC) 3. Restart the computer 4. Go to Start -> Control Panel -> Programs -> Programs and Features, select Avira Internet Security or whichever product you have installed and Change, then click Next until Finish 5. Restart the computer https://answers.avira.com/en/question/-i-am-unable-to-update-or-scan-the-avira-the-error-messages-are-as-follows--the-following-error-occurred-when-trying-to-start-the-update--access-denied-4959 Ik zal overigens nooit aanbevelen om UAC uitgeschakeld te laten. Hoewel niet zaligmakend is ...