1. 检查ADFS服务器的配置，确保用户信息端点已经添加到应用程序的访问控制列表中。
2. 检查代码中的认证参数，确保已经正确设置了ADFS WebProvider的URL和应用程序的客户端ID。
3. 检查用户信息端点返回的信息格式，确保已经正确解析了用户信息并保存到应用程序中。 以下是一个示例代码片段，用于调用ADFS WebProvider用户信息端点并处理可能的401错误：

using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Authentication.Cookies;
using Microsoft.AspNetCore.Authentication.OpenIdConnect;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.IdentityModel.Protocols.OpenIdConnect;

public async Task UserInfo()
{
    var accessToken = await HttpContext.GetTokenAsync(
        OpenIdConnectParameterNames.AccessToken);

    var client = new HttpClient();
    client.SetBearerToken(accessToken);

    var response = await client.GetAsync("https://adfs.example.com/userinfo");

    if (response.IsSuccessStatusCode)
    {
        var json = await response.Content.ReadAsStringAsync();
        // parse user information from JSON and store in application
    }
    else if (response.StatusCode == System.Net.HttpStatusCode.Unauthorized)
    {
        // redirect to ADFS login page to refresh token
        var properties = await HttpContext
            .GetAuthenticationPropertiesAsync(
                OpenIdConnectDefaults.AuthenticationScheme);
        properties.RedirectUri = "/UserInfo";

        await HttpContext
            .ChallengeAsync(OpenIdConnectDefaults.AuthenticationScheme,
                properties);
    }
    else
    {
        return StatusCode((int)response.StatusCode);
    }

    return View();
}