我在本地应用程序和Azure门户中安装了Microsoft Graph。我可以使用自己的帐户成功登录，但当其他员工尝试登录时，我收到了成功的身份验证和访问令牌，但当调用InitializeGraphClientAsync()时，Microsoft.Graph.ServiceException抛出以下内容...

Exception thrown: 'Microsoft.Graph.ServiceException' in System.Private.CoreLib.dll
Failed to initialized graph client.
Accounts in the msal cache: 1.
See exception message for details: Code: ErrorAccessDenied
Message: Access is denied. Check credentials and try again.

登录：

public async Task<string> SignIn()
        {
            // First, attempt silent sign in
            // If the user's information is already in the app's cache,
            // they won't have to sign in again.
            var message = "";
            try
            {
                var accounts = await PCA.GetAccountsAsync();

                var silentAuthResult = await PCA.AcquireTokenSilent(Scopes, accounts.FirstOrDefault()).ExecuteAsync();

                Debug.WriteLine("User already signed in.");
                Debug.WriteLine($"Successful silent authentication for: {silentAuthResult.Account.Username}");
                Debug.WriteLine($"Access token: {silentAuthResult.AccessToken}");
                message = $"Successful silent authentication for: {silentAuthResult.Account.Username}";
            }
            catch (MsalUiRequiredException msalEx)
            {
                // This exception is thrown when an interactive sign-in is required.
                Debug.WriteLine("Silent token request failed, user needs to sign-in: " + msalEx.Message);
                message = "Silent token request failed, user needs to sign-in: " + msalEx.Message;
                // Prompt the user to sign-in
                var interactiveRequest = PCA.AcquireTokenInteractive(Scopes);

                if (AuthUIParent != null)
                {
                    interactiveRequest = interactiveRequest
                        .WithParentActivityOrWindow(AuthUIParent);
                }

                var interactiveAuthResult = await interactiveRequest.ExecuteAsync();
                Debug.WriteLine($"Successful interactive authentication for: {interactiveAuthResult.Account.Username}");
                Debug.WriteLine($"Access token: {interactiveAuthResult.AccessToken}");
                message = $"Successful interactive authentication for: {interactiveAuthResult.Account.Username}";
            }
            catch (Exception ex)
            {
                Debug.WriteLine("Authentication failed. See exception messsage for more details: " + ex.Message);
                message = "Authentication failed. See exception messsage for more details: " + ex.Message;
            }
            await InitializeGraphClientAsync();

            return message;
        }

初始化

private async Task InitializeGraphClientAsync()
        {
            var currentAccounts = await PCA.GetAccountsAsync();
            try
            {
                if (currentAccounts.Count() > 0)
                {
                    // Initialize Graph client
                    GraphClient = new GraphServiceClient(new DelegateAuthenticationProvider(
                        async (requestMessage) =>
                        {
                            var result = await PCA.AcquireTokenSilent(Scopes, currentAccounts.FirstOrDefault())
                                .ExecuteAsync();

                            requestMessage.Headers.Authorization =
                                new AuthenticationHeaderValue("Bearer", result.AccessToken);
                        }));

                    await GetUserInfo();

                    IsSignedIn = true;
                }
                else
                {
                    IsSignedIn = false;
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine("Failed to initialized graph client.");
                Debug.WriteLine($"Accounts in the msal cache: {currentAccounts.Count()}.");
                Debug.WriteLine($"See exception message for details: {ex.Message}");
                await SignOut();
            }
        }

这段代码是直接从微软的一个教程中提取出来的。
Azure ：
API permissions
我将其配置为Accounts in any organizational directory (Any Azure AD directory - Multitenant)