Win 8.1 monthly rollup leaves customers unable to use Microsoft account

If you have Windows 8.1 set to update automatically, you may find you can no longer sign in to your PC with a Microsoft account. Looks like the cause is KB 4038792, the September monthly rollup.

Win 8.1 monthly rollup leaves customers unable to use Microsoft account
OpenClipArt-Vectors (CC0)

This month’s Patch Tuesday brought some weird Windows bugs, but this one’s probably the worst.

I’m seeing reports all over the web that folks running Windows 8.1 aren’t able to log in to their computers using a Microsoft account. Microsoft’s response at this point is that they’re aware of the problem, but if you want to use your machine, you need to log on with a local account.

cannot sign in to ms account Woody Leonhard/IDG

That isn’t a whole lot of help for people who haven’t set up a local account or need to get to something on the machine that’s only available to the Microsoft account.

More than a week ago, in a reply on the Microsoft Answers forum, Microsoft employee Yolvi Ell laid the blame firmly at the foot of this month’s Windows 8.1 update:

This is a known bug in Windows 8.1 after the latest September update. Our Support Engineers are already looking into it and doing their best to resolve it as quickly as possible so as to minimize the inconvenience to our customers.

That would seem to implicate KB 4038792, the 2017-09 monthly rollup for Windows 8.1 and Server 2012 R2. It isn’t clear at this point if the bug also affects the September security-only update for Windows 8.1, KB 4038793.

Ell goes on to say, as of early Monday morning:

As of the moment, affected Windows 8.1 users may use a local account instead of a Microsoft account while our engineers are fixing the bug. We have not yet received any news about when the fix will be released. We'll update this thread once it's available.

How widespread is the problem? I see Microsoft Answers forum posts going back to Sept. 13, the day after the patch was released, here, here, here, here, here, here, here, here and here. There’s a lengthy TechNet thread here. There are discussions on BleepingcomputerMS Power User and Windows Central, as well as an early Japanese-language post on

Those posts describe various parts of the problem, but the common denominator seems to be an unexpected change at the time of this month’s Windows 8.1 security update.

Microsoft is fully aware that their Windows 8.1 customers are getting hung out to dry. Instead of answers, we’re getting pablum.

Still using Windows 8.1? We feel your pain. Drop by the AskWoody Lounge.

Copyright © 2017 IDG Communications, Inc.

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