I've deployed GPO to enforce saving defaults in Office to use OOXML Strict so that compatibility is maintained between OpenOffice (that was the other platform at the time). It worked in my basic test cases, and the 2-3 *nix users that demanded it never hassled me about it from a support perspective. Telemetry is not spying. And no, that is not semantics. Spying would be reporting directly to the NSA/CIA/Whatever that you run a drug ring. To you. Millions of people didn't pay for an upgrade to 10. If you don't pay for something, typically you're the product. I still haven't seen what anyone cares about personally - and only keyboard warriors bring it up to me. I support 1000's of users across different companies and different verticals - precisely ZERO people have engaged me professionally in anyway about advertising in their desktop causing a concern.