Install all updates and reboot the system.If the update fails, from the notification area, click the shield icon > select Virus & threat protection > Check for updates. Manually check for Windows Defender Update try downloading and installing available Windows Update.If it interferes with a pre-installed security application, uninstall the third-party antivirus solution. If you have an additional security application running, check Windows Defender to ensure it has not disabled the updates.Basic fixesīefore getting into more technicalities, try these basic steps to fix the Windows Defender update issue. I might leave Defender on one server and work with MS to find the issue.How to fix Windows Defender is unable to update? 1.

It hopefully will solve the issue for me, but it doesn't explain the cause or truly 'fix' what is broken. I did this on one server and confirmed Defender AV is no longer installed. and run the fltmc command again to confirm. Kindly try to disable the Windows Defender in Manage Roles and Features, untick the Windows Defender feature. You can check by running command prompt as administrator, and run the fltmc command to see what drives are available on the server.

'To assist you with your query Sophos can run with Windows Defender but it's advisable not to run both for we might encounter a performance issue when they run at the same time. Here's what Sophos support said: (my comments in ). It's been my experience in the past that when I install AV, it disables the native Windows AV, but not in this case. I didn't get anything from MS yet, but I also opened a ticket with Sophos, asking about Defender AV and Sophos both running on the same system.

Antivirus microsoft defender windows 7