Why can I not log in to my authenticator

Question

Why can I not log in to my authenticator

Brett Smith 0

Hello!
I have just gotten a new phone and tried to log in to authenticator multiple time and got locked out. Fair enough I reached out for help Wednesday and they said I just had to wait 24 hours to be able to try logging in again because error 400 stops you from attempting when too many attempts happen in too short of a time. Makes sense. I waited until just about 5 minutes ago to be certain enough time has passed. I still cannot log in. I need the authenticator for a lot of separate things for 2 factor authentication and I will be losing complete access to it soon. What am I supposed to do? I am willing to discuss this further over a phonecall or email.

Pauline Mbabu 1,840 Reputation points Microsoft Employee

2026-04-14T20:21:37.9166667+00:00

Hello,

Thank you for reaching out.

If this is a personal account you may need your old device to in order to setup MFA on your new phone, or if you retained the same mobile number you should be able to use this.

Go to www.aka.ms/mfasetup login with your username and password, when it prompts for MFA select "I can't use my Microsoft Authenticator app right now" this should show you your alternative MFA methods if they were setup. - If you don't, you will need access to your old device in order to approve the sign-in. Once you're through this part you should be able to setup a new MFA method.

If this is a work account you're better of asking your IT Support to reset your MFA methods, once they do that you can then go to www.aka.ms/mfasetup to set up the new device.

Your answer

Pauline Mbabu 1,840 Reputation points Microsoft Employee

2026-04-14T20:21:37.9166667+00:00

Hello,

Thank you for reaching out.

If this is a personal account you may need your old device to in order to setup MFA on your new phone, or if you retained the same mobile number you should be able to use this.

Go to www.aka.ms/mfasetup login with your username and password, when it prompts for MFA select "I can't use my Microsoft Authenticator app right now" this should show you your alternative MFA methods if they were setup. - If you don't, you will need access to your old device in order to approve the sign-in. Once you're through this part you should be able to setup a new MFA method.

If this is a work account you're better of asking your IT Support to reset your MFA methods, once they do that you can then go to www.aka.ms/mfasetup to set up the new device.