Anons, I'm making this thread for those still on Win7, but are hesitant on upgrading to Windows 10 due to all the telemetry shit on it.
I've managed to obtain a legitimate ISO of Windows 10 Enterprise, and I'm testing it on an old laptop. I've followed the guides provided by Microsoft to corporations to lockdown the OS and disable telemetry.
archive.is
archive.is
I also followed the guide Hotwheels posted in removing telemetry from Windows 7 systems that had the updates on it. MS was lazy and used the same task scheduler bits in sending telemetry. So you can remove those from it on Windows 10.
Another step I did was disabling and breaking Cortana. This is the process that runs in the background and send data back to MS on a constant basis. This is what lights up wireshark when anyone began to type or do anything on Windows 10. In the above MS guides they tell you to block SearchUI.exe on the firewall to block all outbound connections. However this still leaves it running taking up resources. I simply took ownership of the folder that contained this file and renamed it and the file itself and that broke Cortana, and it no longer appears as a background process.
This also does break in-system search, but installing classic shell explorer returns the old search function from Windows 7 and 8.1.
I'm still testing it on my laptop to see if any updates from MS will restore any of the default settings. However if nothing is changed I can safely upgrade my main system. I do not know if that can be done on Pro, but the Enterprise version is the only one I've tried this on.