You will see the following message: 'We need your phone number with country and region codes.' Confirm that your mobile phone number is being displayed (for example, +18125555555), and then tap Continue.

At the bottom of the screen, tap Sign in.

Be sure 'Auto-detect server' is set to On.

For 'User name', type where 'username' is the username of the account you want to use.For 'Password', type your IU passphrase (but do not press return).

For 'Sign-in address', type your sign-in address, which is usually the same as your primary email address see UniCom sign-in address.

Go to the Exchange admin center and select Mailbox. This is shown in the snippet below In response the Client will now receive a 401 Unauthorized message again and the server will again ask the client to authenticate itself. You can see that in the Client UCCAPI log file. Select User and enter your Lync username. Once the Client receives the pool names it will then Send a SIP REGISTER message to the SFB pool in order to sign in. For the Sign-in Address, enter your Lync username (ie ). Check Your UPN, Primary SMTP, and SIP Addresses Ensure you’re using the same address for your SMTP (Outlook) address, SIP (Skype for Business), and UPN (User Principale Name). Sign in via the phone interface Press the Home button.

If you prefer not to have incoming calls to your work number simultaneously ring to your mobile phone, tap My Info, and then tap Call Forwarding to change your settings. The user name is what you use to sign in to your organization’s network, either or domainusername. Restart the app, log in and check if Skype still asks you to enter your credentials. To change your mobile phone number settings, tap My Info (the last button in the list of menu buttons), then Options, and then Phone Number.

Skype for business sign in