Skype for business authentication using LyncClient

[Ravi Mistry]

I am using LyncClient library to sign-in into SfB through my C# application.

I am using two different office 365 accounts to login into SfB. It works fine for one account while it doesn't work for other account ( this account is using domain created on office 365 account itself).

The problem with second account is though I am providing username & password in BeginSignIn (LyncClient) the another window is popped up for asking password again.

 Edit - Can someone please confirm if the stated issue have to do with the value of "ClientAdalAuthOverride".

ClientAdalAuthOverride - Allowed  - Popup window for password

ClientAdalAuthOverride - Disallowed - works fine

[#2]

Sounds correct, as ADAL is modern authentication, and you would get that popup window:
https://docs.microsoft.com/en-us/skypeforbusiness/manage/authentication/use-adal

[#3]

Thanks Alexander for your response.