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How to read exchange email with unattended console app

I have been trying to implement a solution for this for days. It's my first experiment with Microsoft Graph. I had our network admin register the app and went through the quick start code in console-app-quickstart.
I looked at active-directory-dotnetcore-daemon-v2 and active-directory-dotnet-iwa-v2.
var App = PublicClientApplicationBuilder
.Create("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")
.WithTenantId("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")
.Build();
The PublicClientApplication has the AcquireTokenByIntegratedWindowsAuth function. This sounds good because we can launch the console app as whatever user we want to use with a scheduled task. But it errors out with WS-Trust endpoint not found. Where's WS-Trust endpoint defined?
The sample also includes the line var accounts = await App.GetAccountsAsync() but that always returns zero accounts. Some responses to searches for this say that we have to use the global tenant admin. The company doesn't like that idea at all. How can that be safe? Do we create a new user as an admin tenant just for that?
The other option is this
var App = ConfidentialClientApplicationBuilder.Create("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")
.WithClientSecret("aeiou~XXXXXXXXXXX")
.WithAuthority(new Uri("https://login.microsoftonline.com/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"))
.Build();
The ConfidentialClientApplication doesn't have the integrated windows auth version. I can get connected and get MailFolders and Messages and process those, but it seems to work only when we use App.AcquireTokenForClient(scopes) and API permissions that allow the app to read everyone's email. Security doesn't like that much either.
I also looked at impersonation-and-ews-in-exchange. I read in some places that ExchangeWebService is deprecated and use MS Graph instead. Is the MS Graph API permissions in the EWS category mean that it's going to be around?
Can anyone out there show me the right combination of pieces needed to do this? (api permissions, client application type, scopes, authority, etc). It needs to be unattended (launched by scheduled task), needs to have permissions to read only one email box, and save the attachments.
(sorry so long)
Thanks, Mike

WS-Trust endpoint not found
The WS-Trust endpoint is your ADFS endpoint, if you have ADFS 2019 then MSAL does support that using WithAdfsAuthority see https://github.com/MicrosoftDocs/azure-docs/blob/main/articles/active-directory/develop/msal-net-initializing-client-applications.md
There are some other restriction around using WIA that are listed at the top of https://github.com/AzureAD/microsoft-authentication-library-for-dotnet/wiki/Integrated-Windows-Authentication-in-MSAL-2.x . If the constraints don't affect you it should work okay.
With the Client Credentials flow which is what your using above you can restrict the scope of the mailboxes it can access see https://learn.microsoft.com/en-us/graph/auth-limit-mailbox-access
I would stick with the Graph rather then EWS as the later is being phased out and requires more permissions as its a legacy API.

The tutorial you shared in the question is an asp.net core console app. Since you want to have a console app and use it to read exchange mails.
Therefore, what we can confirm is that: We need to use MS Graph API to read the exchange mails. Graph API required an Azure AD application with correct API permissions to generate Access token to call the API. API permissions have 2 types, Delegated for Web app because it required users to sign in to obtain the token, Application for daemon app like console application which don't require an user-sign-in.
Since you are using the asp.net core console application, you can only using Application API permission. Using Application permission means the console app has the permission to query messages of any email address in your tenant. You can't control the Graph API itself to query some specific users only. But you can write your own business logic to set authorization.
Then we can make the console application authorized to access the API, we can generate an Access token and use it in the HTTP request header to call the API, we can also use the Graph SDK. Using SDK will help to troubleshoot when met error.
using Microsoft.Graph;
using Azure.Identity;
var scopes = new[] { "https://graph.microsoft.com/.default" };
var tenantId = "tenant_id";
var clientId = "Azure_AD_app_id";
var clientSecret = "Azure_AD_client_secret";
var clientSecretCredential = new ClientSecretCredential(
tenantId, clientId, clientSecret);
var graphClient = new GraphServiceClient(clientSecretCredential, scopes);
var messages = await graphClient.Users["{email_address/user_account/user_id}"].Messages.Request().Select("sender,subject").GetAsync();

How to get OAuth2 access token for EWS managed API in service/daemon application

Scenario
I have an Exchange Online environment and service/daemin (no interactive user) application on the Azure VM. Service uses EWS managed API to work with emails in the mailbox of any tenant user. Now EWS client uses Basic authentication that, according to Microsoft, will become unsupported in EWS to access Exchange Online.
Question/Issue
So, I need to find a way to get valid access token for service/daemon application to use with EWS managed API.
My findings
The following article shows an example of using OAuth 2.0 with EWS managed API. This example works, but it uses interactive method of getting consent (sign-in form appears allowing user authenticate themselves and grant requested permission to application) that is not suitable for service/daemon app scenario, because there is no interactive user.
For service/daemon application I need to use client credential authentication flow.
Registered application
Using admin account on https://aad.portal.azure.com portal I registered application with Azure Active Directory. Added client secret for registered application.
Aforementioned article uses https://outlook.office.com/EWS.AccessAsUser.All as a scope. But I did not find permission with such a URL on the portal. I found only the following permissions under Office 365 Exchange Online > Application permissions > Mail:
https://outlook.office365.com/Mail.Read Allows the app to read mail in all mailboxes without a signed-in user
https://outlook.office365.com/Mail.ReadWrite Allows the app to create, read, update, and delete mail in all mailboxes without a signed-in user.
I added both of them and granted admin consent for all users.
Getting access token
For testing purposes and simplicity I did not use any auth libraries (ADAL, MSAL etc.). I used Postman to get access token, then set token variable in debug (see code snippet later in the post).
I tried different endpoints to get acess token.
OAuth 2.0 token endpoint (v2)
POST: https://login.microsoftonline.com/<TENANT_ID>/oauth2/v2.0/token
grant_type=client_credentials
client_id=***
client_secret=***
scope=https://outlook.office.com/EWS.AccessAsUser.All
Sending this request produces the following error response:
AADSTS70011: The provided request must include a 'scope' input parameter. The provided value for the input parameter 'scope' is not valid. The scope https://outlook.office.com/EWS.AccessAsUser.All is not valid.
I tried changing scope to https://outlook.office.com/.default. Access token was returned, but it appeared to be invalid for EWS. EWS client throws 401 error with the following value of x-ms-diagnostics response header:
2000008;reason="The token contains no permissions, or permissions can not be understood.";error_category="invalid_grant"
OAuth 2.0 token endpoint (v1)
POST: https://login.microsoftonline.com/<TENANT_ID>/oauth2/token
grant_type=client_credentials
client_id=***
client_secret=***
resource=https://outlook.office.com
Access token was returned, but also appeared to be invalid for EWS. EWS client throws 401 error with the same value of x-ms-diagnostics response header as described ealier in #1.
Use aquired access token with EWS managed API
Here is code sample that I used to test EWS client with access token acquired in Postman:
var token = "...";
var client = new ExchangeService
{
Url = new Uri("https://outlook.office365.com/EWS/Exchange.asmx"),
Credentials = new OAuthCredentials(token),
ImpersonatedUserId = new ImpersonatedUserId(ConnectingIdType.SmtpAddress,
"user#domain.onmicrosoft.com"),
};
var folder = Folder.Bind(client, WellKnownFolderName.SentItems);

We had a similar problem: We wanted to use a Service Account to connect to a single mailbox and just doing some stuff with the EWS API (e.g. searching in the GAL) and the full_access_as_app seems like an overkill.
Fortunately it is possible:
Follow the normal "delegate" steps
And use this to get a token via username/password:
...
var cred = new NetworkCredential("UserName", "Password");
var authResult = await pca.AcquireTokenByUsernamePassword(new string[] { "https://outlook.office.com/EWS.AccessAsUser.All" }, cred.UserName, cred.SecurePassword).ExecuteAsync();
...
To make this work you need to enable the "Treat application as public client" under "Authentication" > "Advanced settings" because this uses the "Resource owner password credential flow". (This SO answer helped me alot!)
With that setup we could use a "tradional" username/password way, but using OAuth and the EWS API.

You can protect your client application with either a certificate or a secret. The two permissions that I needed to get this to work were Calendars.ReadWrite.All and full_access_as_app. I never tried acquiring my token via PostMan, but use AcquireTokenAsync in Microsoft.IdentityModel.Clients.ActiveDirectory. In that call, the resource parameter I use is https://outlook.office365.com/. It's pretty simple once you know all the little twists and turns. And full disclosure: I was one lost puppy until MSFT support helped me through this. The doc on the web is often outdated, conflicting, or at best, confusing.

You need to register your app in Azure and use certificate based authentication. https://blogs.msdn.microsoft.com/emeamsgdev/2018/09/11/authenticating-against-exchange-web-services-using-certificate-based-oauth2-tokens/

I run into the same issue while following Microsoft official docs for OAuth 2.0 client credentials flow
According to the Microsoft identity platform and the OAuth 2.0 client credentials flow, the scope "should be the resource identifier (application ID URI) of the resource you want, affixed with the .default suffix" (see default scope doc).
So the question is how to convert https://outlook.office.com/EWS.AccessAsUser.All into the resource identifier.
Experimentally I manage to make it working using scope=https://outlook.office365.com/.default. I granted full_access_as_app (Office 365 Exchange Online / Application permissions) and got administrator consent for it.

I did face this issue while implementing OAuth for EWS. My application is not using EWS Managed API. Here is what all I did to make it working.
Added permission Office 365 Exchange Online > full_access_as_app to application.
Acquired access token for scope https://outlook.office365.com/.default.
POST https://login.microsoftonline.com/{tenant}/oauth2/v2.0/token
form-data = {
client_id,
client_secret,
grant_type: 'client_credentials',
scope: 'https://outlook.office365.com/.default',
};
Added access token as Authorization header and ExchangeImpersonation SOAP header to the request.
<SOAP-ENV:Header>
<t:ExchangeImpersonation>
<t:ConnectingSID>
<t:PrimarySmtpAddress>user#domain.com</t:PrimarySmtpAddress>
</t:ConnectingSID>
</t:ExchangeImpersonation>
</SOAP-ENV:Header>

Late answer, but since this seems to come up, and I was just working with this... why not.
If you use Microsoft's v2.0 URLs for OAUTH2 (https://login.microsoftonline.com/common/oauth2/v2.0/authorize and .../common/oauth2/v2.0/token) then the scope for Office 365 EWS is:
https://outlook.office365.com/EWS.AccessAsUser.All
You'll probably want to combine this scope with "openid" (to get the signed in user's identity) and "offline_access" (to get a refresh token). But then offline_access may not be necessary when using client credentials (because you don't have to prompt a human user for them every time you need an access token).
In other words:
params.add("client_id", "...")
...
params.add("scope", "openid offline_access https://outlook.office365.com/EWS.AccessAsUser.All")
If using v1 OAUTH2 URLs (https://login.microsoftonline.com/common/oauth2/authorize and .../common/oauth2/token) then you can use a "resource" instead of a "scope". The resource for Office 365 is https://outlook.office365.com/.
Or in other words:
params.add("resource", "https://outlook.office365.com/")
Note that in the latter case, you're not asking for any scopes (it's not possible to combine "resource" with scopes). But the token will automatically cover offline_access and openid scopes.

I used this method successfully:
Install Microsoft Authentication Library module ( MSAL.PS)
https://www.powershellgallery.com/packages/MSAL.PS/4.2.1.3
Configure Delegate Access as per MSFT instructions: https://learn.microsoft.com/en-us/exchange/client-developer/exchange-web-services/how-to-authenticate-an-ews-application-by-using-oauth
Configure ApplicationImpersonation for a service account as normal
Grab your token
$cred = Get-Credential
$clientid = ""
$tenantid = ""
$tok = Get-MsalToken -ClientId $clientid -TenantId $tenantid -UserCredential $cred -Scopes "https://outlook.office.com/EWS.AccessAsUser.All"

Sign in Webtest Oauth2

Using a full VS Enterprise to do some load testing against our WebApplication, I am struggling to create a webtest that works.
Our tested site is an Azure WebApp/API with an AAD authentication frontend. It is the authenticating as a test user that is failing. While recording with VS or fiddler, I'm failing to playback the test again. I believe it is a credentials/token issue...
As our app is not a Native one, I cannot get a token for a specific users credentials. (I'm getting a known exception)
I have succeeded in getting a Bearer token via the creation of a plugin and its PreWebtest method utilizing the code below however this is at application rather than specific user level.
private string GetAdToken(string inClientId, string inAppKey, string
inAadInstance, string inTenant, string inToDoResourceId)
{
// inToDoResourceId = https://graph.microsoft.com
var myCredential = new ClientCredential(inClientId, inAppKey);
string myAuthority = string.Format(CultureInfo.InvariantCulture,
inAadInstance, inTenant);
var myAuthContext = new AuthenticationContext(myAuthority);
Task<AuthenticationResult> myResults =
myAuthContext.AcquireTokenAsync(inToDoResourceId, myCredential);
return myResults.Result.AccessToken;
}
How can I achieve automation (via the web test) against a specific AAD test user identity to allow further testing automation of our web application?
Thanks in advance,

Thanks for your answers. I found a solution to my problem:
there is a "Set Credentials" button in VS webtest tool where you can add your credentials. when i ran my test again, the test succeeded to sign in to my webapp.
#GuillaumeLaHaye, Yes I know that my AcquireTokenAsync() method was not user-specific but when Im using the one with UserCredential I was getting this exception: The request body must contain the following parameter: 'client_secret or client_assertion'.
because it is a WebbApp/API and not a Native App (configured in Azure Portal, cf. ADAL: The request body must contain the following parameter: client_secret)
#AdrianHHH, Get Ad token was called in a pugin in the preWebtest method (running before every test) with the clientId, clientSecret, tenantId, AadInstance of my web App (I found them on my azure portal)... From this Oauth 2.0 flow, I believe I wanted to get the Authorization code or the access token, but because i'm new in webtesting and Authorization flow, I don't really know which token i got, neither how to use it...
Oauth2.0 flow

OneDrive SDK Authentication Issue in Console App

I am coding against OneDrive SDK within a console application. I am having some trouble trying to authenticate properly. I am curious to see if anyone has done this before or could point me in the right direction?
Code so far:
[STAThread]
static void Main(string[] args)
{
var scopes = new[] {"onedrive.readonly", "wl.signin"};
var msaAuthProvider = new MsaAuthenticationProvider(ClientId, "https://login.live.com/oauth20_desktop.srf", scopes);
msaAuthProvider.AuthenticateUserAsync();
}
Whenever I run my debugger I see the property of isAuthenticated is set to false.

Right now the MSA Authentication only supports Desktop and Windows Mobile Apps as it needs UI to require user sign in which broke in your case because you have a console app. So the problem is to build a IAuthenticationProvider which set the Authorization header in request message like:
public async Task AuthenticateRequestAsync(HttpRequestMessage request)
{
request.Headers.Authorization = new AuthenticationHeaderValue("bearer", await GetAccessTokenFromSomeWhere());
}
The IAuthenticationProvider interface defined in Microsoft.Graph.Core and you can pass it into OneDriveClient constructor so OneDriveClient will make request to OneDrive API for you.
Based on the information you have a console app, I would suggest you look at the code flow for Microsoft OAuth to get an access token and pass it to your authentication proivder.
I am not sure how you can get a code from the OAuth flow, but it seems doable if you fetch it in somewhere and pass it to your console app, then you can make POST request the the code you have to redeem an access token. I have searched for a while and don't find a good example of console app to get OAuth for Microsoft account, sorry. If you find a good way for console app to authentication, feel free to send a PR for MSAAuthenticator.

I succesfully read files from an user without interaction using the OAuth 2.0 Resource Owner Password grant and raw HTTP requests.
There are samples for authentication in daemon applications with application credentials, but first we would need to know how the application was registered and if belongs to a directory in Azure or not because app permissions need to be granted by a directory admin.

Trouble getting test user information

I'm trying to use the Facebook SDK 5.2.1 to ultimately create a test user, however even what I believe is the simple example of getting the list of test accounts isn't working for me. I get the OAuthException "An access token is required to request this resource."
Here's my code (replace APP ID and APP SECRET with my own):
FacebookOAuthClient oauth = new FacebookOAuthClient { AppId = "APP ID", AppSecret = "APP SECRET" };
dynamic tokenRes = oauth.GetApplicationAccessToken();
fbClient = new FacebookClient(tokenRes.access_token);
dynamic response = fbClient.Get("APPID/accounts/test-users");
However, I get the exception on the fbClient.Get line.
Any idea as to what's wrong?
Thanks,
Chad

After hours of trying various things and reading various web pages/blogs, I found the reason it wasn't working. In my app settings, I had my app type set to a Native/Desktop App. Changing this to Web, allows the above scenario to work. I'm not yet quite sure of what other differences exist between web vs native facebook apps. My app is certainly only being used via a desktop application and I can't understand why I need to set this to Web just to allow me to create test users.

This code works in my app:
var app = new FacebookClient(FacebookApplication.Current.AppId,
FacebookApplication.Current.AppSecret);
dynamic result = app.Post(string.Format("{0}/accounts/test-users",
FacebookApplication.Current.AppId),
new { installed = true, permissions = "user_about_me" });

The reason why you are receiving the exception OAuthException is because you have not yet got the permission of the user.
To do a Graph API call on the current user, you need to get the user to accept the permissions that you require FIRST and then do the Graph API call.
You need to get the user to a browser some how in your application, as there is not an authentication flow which doesn't require a browser window.
Check out this URL to view the authentication flows:
http://developers.facebook.com/docs/authentication/