To complete this task, you must have appropriate Office 365 administrator permissions. This article shows how an administrator can reset a user's MFA details, enabling the user to then set up new MFA details at their next log on. However, if this is not completed prior to decommissioning the old device, then administrator assistance will be required to reset the user's MFA details. Individual users may manage their own MFA settings using the online portal at.

A resultant change to MFA details is therefore required if the user is to continue to enjoy access. This is likely to impact MFA and so prevent access to the user's computer. Over time, a user may lose or replace an authenticator device or perhaps move to a new mobile phone number. Multi-factor authentication (MFA) is an authentication method in which a computer user is granted access only after successfully presenting two or more pieces of evidence (or factors) to an authentication mechanism. Resetting an Office 365 user's MFA details

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