Just upgraded my Office 365 ProPlus installation to the new Office 2016 on my computer and noticed that my installation didn’t want to activate when I started up my Office applications. Since I am running Windows 10 and insider I tried the mobile apps and they where running perfect. So there have to be something wrong with my computer, and started to search the Internet if someone noticed the same issues and yes there are.
We’re sorry, something went wrong and we can’t do this for you right now. Please try again later. (0x8004FC12)
I haven’t been able to test the upgrade on a Windows 10 without insider.
[Update] Some folks told me that a Quick Repair from Control Panel > Uninstall or change a program will do the trick, but either this or the Online Repair worked for me.
The solution I found is not nice at all but it works, and as I understand there are some Windows 10 settings that conflicts with the Office activation.
First change some registry keys, that should already exists
HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\ActiveDesktop
NoAddingComponents change from 1 to 0
HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
NoActiveDesktop change from 1 to 0
NoActiveDesktopChanges change from 1 to 0
Run the following commands from an elevated command prompt
net localgroup Administrators LocalService /add
fsutil resource setautoreset true C:\
netsh int ip reset resetlog.txt
And now you have to restart the computer and launch the Word elevated as an administrator.
An activation should appear with the text “Activation was successful”
I just hope this is a temporary problem!
My primary resource:
DeployWindows 
Appreciating the hard work you put into your website and detailed information you offer.
It’s nice to come across a blog every once in a while that isn’t the same unwanted rehashed
information. Excellent read! I’ve saved your site and I’m adding
your RSS feeds to my Google account.
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Its impressive, thanks a lot!!!
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thanks! let me know if there is anything missing
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You are brilliant. I had this error on my surface3, while my PC, (both running win10 and using the same office account) did not have any problem. Everyone had “try this…” blah blah blah.
You listed the steps, I followed, it worked exactly as you instructed.
Thank you, thank you, thank you.
Since I do not know how to fix things without a lot of trial and error, I am commenting on your page to let people know, this worked!
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thanks Jackie! Glad to hear it worked.
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