When you see "Account is locked because user tried to sign in too many times with an incorrect user ID or password" (error code AADSTS50053), this is due to smart lockout protection. The lockout triggers after 10 failed attempts (or 3 for US Gov clouds).
The AADSTS50034 error occurs because the user account does not exist in the target Microsoft Entra ID (Azure AD) tenant.
A passkey is a digital credential that enables a user to log into an online service without having to enter a password. Instead, the user authenticates using the device-based authentication factor that is already unlocked on their device.
Multi-Factor Authentication (MFA) blocks 99.9% of account compromise attempts. But attackers are finding ways around it. The remaining 0.1% of attacks target specific weaknesses like token theft (up 111% in 2024), MFA fatigue, SIM swapping, and Adversary-in-the-Middle (AiTM) tactics.
You get AADSTS50027 when Azure AD rejects a JWT token because it's malformed, has the wrong audience, expired, or fails signature validation. This typically happens during app authentication
Outlook or Teams shows error AADSTS50053 with message "Your account is locked" or "Sign-in blocked." Azure AD Smart Lockout has temporarily locked the account after too
When a user gets AADSTS50144: InvalidPasswordExpiredOnPremPassword in a hybrid identity setup, it means their on-premises Active Directory password has expired. Azure Entra ID (formerly Azure AD) cannot authenticate with the
When signing in to a Microsoft 365 application or Azure service, error AADSTS50064 with the message "CredentialAuthenticationError - The credential used to authenticate with the authentication scheme 'X509Certificate&
Microsoft Entra Connect sync fails with AttributeValueMustBeUnique error when two or more objects in your on-premises Active Directory share a unique attribute like userPrincipalName or proxyAddresses. The sync error log
Outlook or Teams shows error AADSTS50076 with message "Due to a configuration change made by your administrator, you must use multi-factor authentication." An MFA policy (Security Defaults, per-user
Users signing in to Microsoft 365 or Azure services may see "Your sign-in was successful but does not meet the criteria to access this resource" or error code
When a user tries to sign into an Azure-connected application, they get the error: "AADSTS50034: The user account does not exist in the directory. To sign into this application,
