unable to sign In for MultiTenant Azure AD using Custom policies in AAD B2C from my asp.net core web app

Question

I have set up multitenant sign in sign up in Azure AD using a B2C custom Policy.

After uploading the policy and testing using Run Now button in Azure portal with a reply url https://jwt.ms and everything worked as expected, I got the token and my user name etc.

When I try to sign in with my web app sign in, a dialogue box appeared, when i choose to sign in with social accounts and I pick my AAD Tenant it does not work and results in an error with endpoint:

https://localhost:{myport}/MicrosoftIdentity/Account/Error 

with no specific error code.

I am interested in help on how to debug and resolve this.

Answer 1

Use the Azure B2C standard customer policy starterpack .

Follow this document to configure the multi-tenant sign-in.

The most important thing is configuring ValidTokenIssuerPrefixes in the TechnicalProfile .

The format is:

<Item Key="ValidTokenIssuerPrefixes">https://login.microsoftonline.com/{tenant id of tenant A},https://login.microsoftonline.com/{tenant id of tenant B}</Item>