Asp.net mvc OWIN SSO的外部登录信息为空,错误=访问被拒绝

Asp.net mvc OWIN SSO的外部登录信息为空,错误=访问被拒绝,asp.net-mvc,asp.net-identity,single-sign-on,owin,Asp.net Mvc,Asp.net Identity,Single Sign On,Owin,我正在实现SSO。当调用ExternalLogin方法时,SSo页面打开,我输入凭证,它转到回调操作ExternalLoginCallback。但是,在下面的代码中loginInfo为null。我在URl中也得到了error=access\u denied var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();

我正在实现SSO。当调用ExternalLogin方法时,SSo页面打开,我输入凭证,它转到回调操作ExternalLoginCallback。但是,在下面的代码中loginInfo为null。我在URl中也得到了error=access\u denied

var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();