Could not resolve type with token 01000021 from typeref

Question

I am trying to create virtual appointments based on this documentation:
https://learn.microsoft.com/en-us/graph/api/application-post-onlinemeetings?view=graph-rest-1.0&tabs=csharp

Here is my code:

            InteractiveBrowserCredentialOptions options = new()
            {
                TenantId = B2CConstants.TenantId,
                ClientId = B2CConstants.ClientId,
                AuthorityHost = AzureAuthorityHosts.AzurePublicCloud,
                // MUST be http://localhost or http://localhost:PORT
                // See https://github.com/AzureAD/microsoft-authentication-library-for-dotnet/wiki/System-Browser-on-.Net-Core
                RedirectUri = new Uri("http://localhost"),
            };
            // https://learn.microsoft.com/dotnet/api/azure.identity.interactivebrowsercredential
            var interactiveCredential = new InteractiveBrowserCredential(options);
            GraphServiceClient graphClient = new(interactiveCredential, B2CConstants.Scopes);
            var onlineMeeting = new OnlineMeeting
            {
                StartDateTime = DateTimeOffset.Parse("2023-02-17T18:00:34.2444915+00:00"),
                EndDateTime = DateTimeOffset.Parse("2023-02-17T18:30:34.2464912+00:00"),
                ExternalId = Guid.NewGuid().ToString(),
                Subject = "User Token Meeting"
            };
            try
            {
                await graphClient.Me.OnlineMeetings
                    .Request()
                    .AddAsync(onlineMeeting);
            }
            catch (Exception ex)
            {
            }

AddAsync() throws an exception:

{Status Code: 0
Microsoft.Graph.ServiceException: Code: generalException
Message: An error occurred sending the request.

 ---> System.TypeLoadException: Could not load type of field 'Microsoft.Graph.TokenCredentialAuthProvider+

Answer 1

Hi @Dmitriy Reznik

I tried creating an online meeting using the graph C# SDK and it worked fine. Refer to the sample code:

using Azure.Identity; 
using Microsoft.Graph;


var scopes = new[] { "OnlineMeetings.ReadWrite" };

var tenantId = "{tenant id of the azure ad}";

// Value from app registration
var clientId = "{client id}";

// using Azure.Identity;
var options = new TokenCredentialOptions
{
    AuthorityHost = AzureAuthorityHosts.AzurePublicCloud
};

var userName = "{user name}";
var password = "{password}";

// https://learn.microsoft.com/dotnet/api/azure.identity.usernamepasswordcredential
var userNamePasswordCredential = new UsernamePasswordCredential(
    userName, password, tenantId, clientId, options);

var graphClient = new GraphServiceClient(userNamePasswordCredential, scopes);

var onlineMeeting = new OnlineMeeting
{
      StartDateTime = DateTimeOffset.Parse("2023-07-12T21:30:34.2444915+00:00"),
      EndDateTime = DateTimeOffset.Parse("2023-07-12T22:00:34.2464912+00:00"),
      Subject = "Test Meeting"
};

try
{
   await graphClient.Me.OnlineMeetings
   .Request()
   .AddAsync(onlineMeeting);
}
catch (Exception ex) { 

      Console.WriteLine(ex);
}

By the way, based on my tests, creating an online meeting in an Azure B2C tenant is not currently supported.

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