This has been going around on the ‘Net the past few days. It has been found that Windows 10 uploads data to its servers even when every “feature” and app that normally might be expected to do that is disabled/uninstalled. For example, even if you don’t use the Cortana voice-command feature or Bing search, stuff is still being uploaded to Microsoft servers related to this. And even when users choose to not participate in any sort of customer improvement options and disable any kind of tracking, it is still tracking and uploading things.
Not only is this a big privacy issue, there is also a system performance issue, as extra CPU cycles must be run and disk and network activity must occur to process these telemetry-related tasks.
And it is also the case that Windows 8.1 and 7 also are now doing this. Microsoft has been adding all these telemetry and tracking aspects to them lately through Windows Update, making them closer to Windows 10.
The advice from many experts now is to not go near Windows 10. Do not install it. Retain your privacy and control over your systems.
Below are instructions for disabling the unwanted telemetry/tracking in Windows 7 and 8.1