How do I get Cortana and Messaging to work in Windows 10 on my HTC One (M8)?

Joerees

I upgraded my HTC One phone (M8) to Windows 10. Since then, Cortana only works in typing mode, and Windows Messaging does not open at all. When I try to open Messaging, I get a message:

"Can’t open messaging
Before we can open the messaging app, you’ll need to go to Settings>Privacy>Contacts and turn on messaging."

When I go to Settings>Privacy>Contacts, I see a list of apps (including Cortana and Messaging), and each has an on/off "slider" that is grayed out. But I cannot turn any of them on! There is no other place to go from that screen, except to the Microsoft Privacy website, where there are hundreds of pages of licensing information, but no place to "accept" the agreement. The only other place to go is back to the phone's home screen.

And despite what I've seen in Microsoft help sites, there is not button anywhere for rolling back to Windows 8.1

Has anybody else had this problems? If so, did you solve it? If so, how?

Verizon_Support

We want to ensure that you are able to use all the features that you desire to when it comes to your device. I appreciate the steps you've taken. Have you ever had this working? If you follow these steps http://vz.to/1YzdJyH does this seem to help/work?
ErinW_VZW
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