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A Windows insider has confirmed the issue on his virtual machines that all Windows 7/8/8.1 operating systems updated to the definition version running full scan are affected but other machines that haven’t upgraded to the latest version can perform the full scan without any issue.īesides, when reading comments posted on social media and support forum Windows 7, Windows 8 and 8.1 systems running Microsoft Security Essentials and Windows Defender with the latest definition version are affected. Even some System Center Endpoint Protection users are also reporting this issue and have been guessing that a faulty virus definition could be the factor.Īctually, the error seems to stem from a buggy 1.289.1521.0 definition update issued on March 19.2019 for Microsoft antimalware solutions. Besides, there are more reports of the same problem on Microsoft Social Technet forum and Reddit forum. Now we don’t know how many users are affected by this problem but have seen early reports of this on AskWoody website. For Windows 10 users, they seem to not be affected.Ĭompared to Windows Defender, Microsoft Security Essentials offers a fuller range of protection against malicious software since it can prevent PC from viruses, worms, spyware, Trojans, rootkits, and more. The problem is happening with some users, but not all.
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Tip: Windows Defender cannot work or cannot be turning on? This post - Full Fixes for Windows Defender Not Turning on in Windows 10/8/7 may be you are looking for.īesides, when manually running Security Essentials or Windows Defender scan on a computer running Windows 7, 8 or 8.1, the antimalware solutions are crashing randomly with an error message informing them PC couldn’t be scanned and Windows suggests restarting the computer to start antivirus service, and shows the error code 0x800106ba.
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