Outlook on mobile iOS mobile device doesn't work due to authenticator app

Hi @Aaron Pearsall,

Thank you for reaching out regarding the issue with signing in to Outlook on your iOS device.

Based on your description, it appears that the Microsoft Authenticator app is prompting for number matching, which is a security feature designed to enhance account protection.

To better assist you, could you please clarify the following:

• Have you previously set up the Microsoft Authenticator app on any device for this account, or is this your first time trying to sign in?   
• If so, are you currently using the same device where you originally registered the Authenticator app? Have you recently switched to a new device?
• Are you still able to sign in to Outlook on the web and the Outlook desktop app without any issues?

While we wait for your response, here are some steps you can try to resolve this:

1/ Verify the sign-In process

• When you sign in to Outlook, the app will display a number.
• In Microsoft Authenticator, you should see a prompt with a text box to enter that number. If you only see numbers without an input field, the app may need to be updated or reconfigured.

2/ Alternative access

• If you need immediate access, you can use Outlook Web App via Safari or Chrome on your mobile device.

3/ Add another security method

If you still have access to the account on your computer:

Sign in to the Security info page of your admin account at mysignins.microsoft.com/security-info.

Select Add sign-in method.

From the pop-up, see if there is an option for "Phone", then choose Phone.

Enter your phone number and follow the on-screen steps to complete the setup.

Once added, try signing in using the text message option.

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.   

If you have any updates, feel free to leave a comment under this post. I’ll be happy to assist further.  

Thank you for your cooperation and understanding in resolving this matter.

I look forward to continuing the conversation.

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Thank you for responding. This has been extremely disruptive, and I'm hoping we can get to a resolution soon. I'll first answer the bullet points asked:

• Yes i've previously set up authenticator on a device and it worked fine
• I am on a new iOS iphone 17 Pro which is where to problem first occurred
• I am able to sign into outlook on the web and desktop just fine

As to the resolve steps listed,

• When i try and add my work email credentials into the outlook app, it immediately shifts me to the authenticator app where it displays the two digit numbers, instead of prompting me to enter the two digits like the recommendation suggests. There is nowhere to enter the code at this point. I would expect exactly what the recommendation suggests, but this isn't the case
• I have access on my computer, so not necessary to try different browsers

I need a solution here. I'm willing to drive somewhere, screen-share, phone call, whatever it will take to fix this issue. I'm somewhat astonished that this issue is even possible to exist given new technology upgrade, and with todays platforms. Please, suggest something for a solution.