From techradar:
More adverts will be coming to Windows 10 with the big Creators Update which arrives in April, you’ll probably be not so pleased to hear.
There are already adverts scattered around the OS, most prominently on the Start menu and lock screen, and now they will be coming to the integrated Share interface which is being overhauled for the Creators Update.
As Winaero reports, the new Share box now appears in the middle of the screen rather than in the sidebar, and it features not just apps you have installed on your PC and can share files with, but ‘recommended apps’. Adverts, in other words.
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Presumably you’ll be able to disable this feature, as you can do with the adverts elsewhere in Windows – if you don’t want ads on the lock screen, it’s easy enough to turn them off.
But naturally these things are all on by default, and may never be touched by more novice users. That said, inexperienced computer users may even appreciate the suggestions, although obviously these recommendations are taking up space where actual ‘live’ icons (for installed apps) could be displayed.
Don't worry -- by the time they're done, I'm sure that Microsoft will have found a way to plaster these kinds of "recommendations" on every nook and cranny of Windows 10, no matter how obscure or infrequently-travelled. Windows 10 was not free; it just didn't cost you anything up front. If you're not being asked to pay up front, then you are the product.