Hi @Aman Pareek · Thank you for reaching out.
Microsoft Graph API is federated with Azure AD, which is why it will trust only the tokens which are issued by Azure AD. The only way I can think of achieving this requirement is by federating OKTA with Azure AD. That way, after the user is authenticated via OKTA, token will be sent to Azure AD; Azure AD can then validate the token and issue a corresponding token to be used by Microsoft Graph API.
Read more:
https://help.okta.com/en/prod/Content/Topics/Provisioning/azure/azure-integrate-main.htm
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