Delivery Optimization in Windows 10 can reduce the bandwidth that Windows Update uses by retrieving updates and apps from other Windows 10 devices on your local network. It also has the ability to get these same updates from other PCs on the Internet to speed up their delivery.
This setting is turned on by default when you install or upgrade to Windows 10. Microsoft has clearly stated that no personal information about your system or personal files is viewed, copied or shared by this feature however, it is understandable that some users will not want this activated on their systems.
Here are the steps to turn off Delivery Optimization for Windows Update or, if you have previously turned it off, you can use the steps to turn it back on.
Step One: Open Windows Settings > Update & Security Settings Page
Step Two: Open Windows Update & Security Advanced Options
Step 3: Open Choose how updates are delivered options
Step 4: Turn Windows Update Delivery Optimization Off or On
As I mentioned earlier, this setting is turned on by default so if you simply want to turn it off then just toggle the On/Off option (#1) to off. At this point you can exit the Windows Settings app and return to normal use of your system.
If you want to keep Delivery Optimization turned on and just limit the scope to your local network then select that option next to #2 and keep #1 toggled to On.
You can read more about Delivery Optimization and specifics relating to privacy on the Windows Update Delivery Optimization: FAQ.
Be sure to check out all of our Windows 10 Anniversary Update Coverage.