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"...And again in other words: I Demand a full working OS..."
I'm afraid all the demanding on your part does not constitute a fulfillment command on Microsoft's part

werby said:

I demand because they sell it...

You got it, exactly as EULA goes. It was clear from the beginning of W10, that it's a "service" and there will be changes during it's lifetime.

werby said:

"Changes" is not a synonym to "Failures".

This particular happening is "planed obsolescence" to downplay certain feature until it is completely removed. It is just a change and not failure. Backup functions are also going away but slowly and yes it would've been better if they just announced that they are killing those features and than just kill them completely so users know not to count of them. Personally I would be glad to leave those functions to 3rd party programs.