There’s reports that Microsoft Windows 7 devices that are Domain Joined, and have unmanaged WUA\WSUS settings can lead to Win10 being downloaded, wasting about 3GB in the process.
If the ConfigMgr Agent is on the device but the Software Updates Management feature is not switched on, the Client will not be configured with WSUS settings, and will result in the download taking place the next time Microsoft Updates is checked.
I think an easy way to solve this while Microsoft figure out how to stop this is to setup a Group Policy, set WSUS settings and apply it to the the Win7 devices that are affected by the above activity. This will stop them from contacting Microsoft Updates, and in the meantime you should be adding them to your patch cycle so that they are managed properly.
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