A friend asked me to check his antivirus, defender will not start no matter what I do, I have followed many suggestions as to how to get it to start, none worked. He had newest version 1709, he did have webroot and took it out so defender should start, it will not, it says sorry we have a problem please try again, trying again does nothing.
Turn On or Off Windows Defender in Windows 10 Security System Tutorials
You can also try to run this as admin:
[Batch] Windows Defender Enable - Pastebin.com
he did have webroot and took it out
Did he use an uninstall tool for Webroot or the Windows Control Panel uninstall ? A cursory glance while trying to find a link indicates Webroot may be difficult to uninstall which may be effecting Defender.
If the links provided above by TO do not work, may want to research and find an uninstall tool (if not previously used). If necessary, may want to download RevoUninstaller. Also, manually check the registry (regedit) and file explorer (folders) to delete any Webroot entries.
Final option would be to reset or reinstall Win10.
Reset Windows 10
If you didn't use an uninstaller from Webroot there may be fragments left in your system that are preventing Defender from starting. You can d/l the removal tool & run it if you haven't done that yet.
If you are still encounter difficulties installing the Webroot security software, please re-download and save the Webroot WRUpgradeTool.exe upgrade/cleanup tool to your Desktop by clicking here.
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