Windows Defender cannot be started on Windows Server 2012/2016 - must be manually started

Hi Björn Lagerwall,

Did you try restart any of the servers after uninstalling Sophos? It might simply require a restart, as Windows probably doesn't know or has its information updated that the third-party antivirus software has been removed.

Another way would be to simply script this with PowerShell to go through all affected 150 servers (for example make a list), have the script iterate though the list and start the Windows Defender service (WinDefend).

Example:

Get-Content "C:\Temp\ServerList.txt" | ForEach-Object {
Start-Service -Name "WinDefend"
}

Best regards,
Leon