MFA & Verification Issues

How to Fix Microsoft 365 Mobile Apps Signed Out and Authenticator Inaccessible

Khadija Khan Sep 29, 2026 868 views

Question details

The user is unexpectedly signed out of Microsoft 365 mobile apps and cannot sign back in because the Microsoft Authenticator app is inaccessible.

How to Fix Microsoft 365 Mobile Apps Signed Out and Authenticator Inaccessible

Product: Microsoft 365
Device & OS: not provided
Scenario: Attempting to sign back into Microsoft 365 mobile applications, such as Teams, OneDrive, and Outlook.
Observed behavior: The sign-in process cannot be completed because the Microsoft Authenticator app is unavailable or inaccessible, completely locking the user out of their mobile apps.

Before you start

Check your internet connection and verify if you have previously set up alternative multifactor authentication (MFA) methods, such as a phone number for SMS or a secondary email address.

Solution 1Recommended

Use an Alternative Verification Method

Use this solution if you have previously registered a backup verification method, such as a phone number, to bypass the inaccessible Authenticator app.

Microsoft 365 allows users to configure multiple verification methods. If the Authenticator app is unavailable, you can often use a text message (SMS) or a voice call to authenticate your sign-in attempt.

Navigate to the Office login page

Open a web browser on your computer or mobile device and go to https://office.com.

Enter your credentials

Click 'Sign in', enter your Microsoft 365 work or school email address, and input your password.

Select a different verification option

When prompted to approve the sign-in using the Authenticator app, click the link that says 'Sign in another way' or 'Use a different verification option'.

Choose an available backup method

Select an available phone number, text message, or voice call option from the list. Enter the verification code you receive to complete the sign-in.

Successfully Signed In: Once signed in, you can manage your security info from your account settings to re-add or fix your Authenticator app.

Solution 2

Contact Your IT Administrator for an MFA Reset

Use this method if no alternative verification methods are available or if you are completely locked out of your account.

Free Microsoft Office alternative

Use WPS Office for a Hassle-Free Experience

If you frequently encounter complex authentication loops or enterprise lockouts that prevent you from editing your documents, consider using WPS Office. It provides a lightweight, local, and accessible environment to work on your files without relying strictly on enterprise cloud authentication.

1. Download WPS Office: Visit the official WPS Office website or your device's app store to download the free application.
2. Install and Launch: Follow the simple installation prompts and open the WPS Office application on your device.
3. Open Your Documents: Tap 'Open' and select any local Word, Excel, or PowerPoint files to start editing immediately without enterprise cloud restrictions.

No complex enterprise MFA hurdles required for local offline editing.Fully compatible with Microsoft Office formats like DOCX, XLSX, and PPTX.Lightweight, fast, and highly responsive on both mobile and desktop devices.Includes Word, Excel, and PowerPoint alternatives in one single app.

microsoft office alternative - wps office

Frequently Asked Questions

Why did Microsoft 365 suddenly sign me out of all mobile apps?

This usually happens due to a recent password change, an expired authentication token, or an update in your organization's security policies forcing a re-authentication for security purposes.

Can I reset the Microsoft Authenticator app myself?

If you are entirely locked out of your account and have no alternative verification methods (like an SMS number) configured, you cannot reset it yourself. You must contact your IT administrator to perform the reset.

What alternative verification methods can I use instead of the app?

Depending on what your organization allows and what you previously set up, you can use SMS text messages, automated voice calls, hardware security keys, or a secondary email address to verify your identity.

Login & Account Issues