# AADSTS errors

> This section includes a list of possible errors related to Azure Active Directory (now called Microsoft Entra ID) and their corresponding Azure Active Directory Security Token Service (AADSTS) error codes.

This section includes a list of possible errors related to Azure Active Directory (now called Microsoft Entra ID) and their corresponding Azure Active Directory Security Token Service (AADSTS) error codes.

These errors occur when a UiPath resource tries to call the Microsoft Graph API endpoint and runs into an authentication error. 

For a comprehensive list of AADSTS error codes, see [Microsoft Entra authentication and authorization error codes](https://learn.microsoft.com/en-us/entra/identity-platform/reference-error-codes).

:::note
The steps and/or screenshots described in the following sections may differ in the newest Microsoft UI.
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