From Woody Leonhard at InfoWorld:
A bad patch distributed the day before Windows 10 Anniversary Update’s release has taken out Cortana on many machines. Yesterday, I wrote about the build 14393.10 patch, KB 3176929, which Microsoft distributed to beta testers on the night of Aug. 1. I have no idea why Microsoft patched the Anniversary Update on the night before its long-anticipated general release.
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Many threads I’ve seen on the Microsoft Answers forum and elsewhere are simply incorrect. Users didn’t do anything to bring on the problem. It’s a bug that appears in some copies of one, specific version of Windows 10 Anniversary Update. Unfortunately, that version of Win10 AU was rolled out to a few hundred million people on Aug. 2 -- and it’s still rolling out, even as we speak.
This Cortana bug is different from the language snafu that has disabled Cortana before. It isn’t related to Cortana being pulled from Education editions. It’s directly attributable to build 14393.10. And yes, the bug was introduced the night before the big rollout.
I haven’t seen any fixes that work. If you’re in the Insiders program and roll back to beta builds 14393.0 or 14393.5, Cortana returns. If you’re not in the Insiders program and you have this problem, you can roll back to the Fall Update 1511 (Start > Settings > Update & security > Recovery, Go back to an earlier build), which takes quite a while.
That’s assuming you actually want Cortana, which is by no means a given.
Microsoft’s in an interesting quandary right now. If the ‘Softies release a manual workaround, chances are pretty good somebody will figure out a way to reverse the steps in the workaround and allow anyone to turn off Cortana. That would be something of a Holy Grail in some circles, as Microsoft makes it very difficult to turn off Cortana in the Anniversary Update.
If the ‘Softies release a patch -- perhaps yet another cumulative update for its newly released product -- some will be tempted to simply block the cumulative update and thus retain control over Cortana.
Let’s hear it for last-minute patching.And people wonder why it's a bad thing that users don't get to control their PCs' updates in Windows 10 Home. Holy shit show, Batman!
If you really love Cortana, though, don't worry -- there actually is a workaround.
Also from Woody Leonhard at InfoWorld:
As best I can tell, a self-described Computer Science student with the handle Ambious first posted the solution on the Microsoft Answers forum:
1. Start the Registry Editor (type regedit in the search box)
2. Navigate to
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Search
3. And change the key BingSearchEnabled from 0 to 1
You may have to log off, then back on again, but some report that it works straightaway. Ambious also advises to make sure that all the Cortana flags are set to 1. On the machines I’ve seen, that means you should ensure CanCortanaBeEnabled and CortanaConsent are set to 1.
But there are two problems:
First, Microsoft hasn’t endorsed this approach. Microsoft has had two days and hundreds of publicly visible complaints (not to mention more than a hundred Feedback Hub complaints) and, as best I can tell, there’s been no official acknowledgment -- and this fix has been ignored.
And second, we don’t know if there are any undesirable side effects to the change. Everything I’ve seen says that setting BingSearchEnabled to 1 is innocuous. But if that’s the case, why is there a Registry entry for it in the first place? Is there something we don’t know about?
Microsoft managed to push the 14393.10 patch less than 24 hours before the general rollout of build 1607. You’d think they could've posted a manual fix in a similar timeframe.
Behold! Microsoft's legendary customer service in action: adding bugs to forced updates at the last second, and then maintaining radio silence while customers sort it out for themselves.
In his previous day's article on this same bug, Leonhard mentioned that a manual workaround would make it possible for tech-savvier users to manually disable Cortana at will. Now, I might be mistaken, but I think that's just happened.
Logically, if setting Cortana's flags to 1 via a registry edit can turn Cortana back on when Microsoft had accidentally turned it off, then setting all those same flags to 0 should have the reverse effect. I haven't tried this, mind you (and can't, since I'm not running Windows 10), but it seems like the problem was that users didn't know where to go, in order to make the changes, and they've now solved that problem for themselves. Crowd-sourcing for the win!