I am trying out the Azure AD-B2C. The user signup/sign in is fine when the MFA is turned off. But when I turn it on, and the user tries to sign in and provides the phone number, and requests a text message by clicking "send code", I get the Http 400 error: size of request headers is too long. Anybody else have this issue?
This issues is usually caused by a corrupted cookie that is too long. Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences). If clearing cookies didn't help then it is possible that the cookies.
The "Request header too large" message is thrown with an HTTP error code 400. This error occurs if the size of the request header has grown so large that it exceeds the maximum-allowed size. We recommend that you use the latest version of the SDK.
The HTTP 431 Request Header Fields Too Large response status code indicates that the server refuses to process the request because the request's HTTP headers are too long. The request may be resubmitted after reducing the size of the request headers.
The error HTTP 400: Size of header request is too long generally happens because there's too many cookies.
Azure AD B2C's login goes through login.microsoftonline.com, as does almost every Microsoft service (O365, Azure, etc). So if you've got several accounts that you've signed in to across these services, you're accumulating cookies that will cause this problem.
Clearing the cookies should resolve this problem. If this is happening on a recurring basis, you should edit your question to include details about the request and cookies in order to best figure out what's bloating the request and how to reduce it.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With