Windows Defender on Server 2016 slows sequential file write to a crawl
On windows server 2016 Windows Defender under Terminal Services slowed down sequential file writes by a factor of 100. We output .csv files to a directory as the first step of loading them into an excel report in our application. We do not get reports of virus or other problems, but none the less, it requires we deinstall defender to get our application to perform properly.
We are a Microsoft partner and were able to confirm this behavior on multiple servers.