Microsoft Azure, Office 365 users hit by multi-factor authentication issue

A number of Microsoft Azure and Office 365 users have been unable to get into their accounts for most of the day on November 19. The problem: A multi-factor authentication issue which hit users worldwide and left them unable to sign into their services.

The Office 365 status page noted that affected users may be unable to sign in using multi-factor authentication (two-factor authentication) and may also be unable to do self-service password resets.

"A subset of users are no longer receiving prompts on their mobile devices (SMS, call or push) and (we) are investigating diagnostic logs to understand why," the status dashboard noted.

ZDNet: Black Friday 2018 deals: Business Bargain Hunter's top picks | Cyber Monday 2018 deals: Business Bargain Hunter's top picks

Azure and Office 365 MFA services were affected starting at 4:39 am UTC (which was 11:39 pm ET the previous day), according to the Office status page.

The Azure status page noted that those affected may have had problems signing into Azure resources like Azure Active Directory, when MFA was required.

Azure engineers reported around noon ET today that they had deployed a hotfix , but that it took time to take effect across impacted reasons, and in particular Europe and Asia-Pacific. Engineers were reporting they have seen a reduction in authentication errors as a result of the hotfix. The hotfix also tipped off engineers that some subset of customers were not receiving SMS, Call or Push prompts for MFA.

"Engineers are continuing to explore additional workstreams and potential impact to customers in other Azure regions to fully mitigate this issue," the Azure status page noted.

CNET: Black Friday 2018: The best deals on sale right now | The best Black Friday deals of 2018: The Cheapskate's picks | Black Friday 2018 Amazon deals now available

Beyond those status reports, Microsoft hasn't shared information as to what caused the MFA services problem today.

Update (4:30 pm ET): I'm hearing from more users that the MFA issue seems to be mostly over. The Azure status page now says all services are running normally. The Office 365 status page says:

"We've observed continued success with recent MFA requests and are taking additional actions in the environment in an effort to prevent new instances of this problem. Our investigation into the root cause of this problem is ongoing and maintained as our highest priority.

Update (November 21): According to a preliminary root cause analysis provided by MIcrosoft on its Microsoft 365 Admin Health Center:

"A recent update to improve conections to caching services for the MFA service introduced an issue that prevented users from being able to sign in or carry out self-service password resets when using MFA for authentication."

Best gifts for co-workers under $50 on Amazon

Best Black Friday 2018 deals:

• Amazon Seven Days of Black Friday Deals: All-time lows on office devices
• Amazon Black Friday 2018 deals: See early sales on Echo, Fire HD
• Best Buy Black Friday 2018 deals: Deep discounts on Apple Mac, Microsoft Surface
• Target Black Friday 2018 deals: $250 iPad mini 4, $120 Chromebook
• Walmart Black Friday 2018 deals: $99 Chromebook, $89 Windows 2-in-1
• Dell Black Friday 2018 deals: $120 Inspiron laptop, $500 gaming desktop
• Newegg Black Friday 2018 deals: $50 off Moto G6, $70 off Nest thermostat
• Office Depot Black Friday 2018 deals: $300 off Lenovo Flex, $129 HP Chromebook
• eBay Black Friday 2018 deals: See early sales on Galaxy Watch, Chromecast
• Lenovo Black Friday 2018 deals: ThinkPad laptops and more
• Microsoft Store Black Friday 2018 deals: Ad showcases Surface, laptop deals
• Windows laptops Black Friday deals: Dell, HP, Lenovo
• Chromebook Black Friday 2018 deals: Dell, Google, HP
• Best tablet Black Friday deals: Apple iPad, Amazon Fire
• Black Friday 2018 iPhone deals: $400 iPhone X gift card, BOGO iPhone XR
• Black Friday 2018 smartphone deals: OnePlus 6T, LG G7

Previous and related coverage:

Windows 10 1809 big iCloud problem: We're working on fix, say Microsoft, Apple

Microsoft blocks the Windows 10 October update for iCloud users, while incompatibility problems also hit F5 Network's VPN.

Microsoft: We've pulled buggy Outlook 2010 patches over crashes

Flawed updates cause Outlook and other apps to crash.

Microsoft resumes rollout of Windows 10 version 1809, promises quality changes

After a delay of more than five weeks, Microsoft has resumed the rollout of the Windows 10 October 2018 Update. The company also promised sweeping changes in the way it approaches quality issues, including better communication with customers.