In ADAL.NET 2.x, we use the below code to acquire token from Azure AD using UserCredential and it works perfectly:
var authContext = new Authen
FYI, it seems as though they have removed this functionality from ADAL. source
To authenticate with a users username/password combo, I believe you will have to use HttpClient and make the post request yourself.
Post to:
https://login.microsoftonline.com/yourdomain.onmicrosoft.com/oauth2/token
with:
resource={resource}&client_id={clientid}&grant_type=password&username={username}&password={password}&scope=openid&client_secret={clientsecret}
in the request