AudioCodes 400HD Series - 8 Troubleshooting; Unable to Sign in to Skype for Business Using Username;Password; Unable to Authenticate User Using PIN; IP Phone Fails Registration Process

Administrator's Manual 8. Troubleshooting
Version 3.4.4 195 400HD IP Phones Series - Teams Compatible
8 Troubleshooting
This section provides various troubleshooting procedures.
8.1 Unable to Sign in to Skype for Business using
Username/Password
Problem
Unable to sign in to Skype for Business using the
username/password sign-in method.
LCD Message
"Invalid address, username or password"
Corrective Actions
1 Make sure you correctly entered the sign-in address, username, and password.
2 Make sure you have the correct username/password; it may have changed in the
Enterprise's Active Directory.
3 Make sure you used the correct sign-in method (Sign-in softkey > Switch sign-in
method > OK hard key or Select softkey).
8.2 Unable to Authenticate User using PIN
Problem
Unable to authenticate user when signing in to Skype for Business
using PIN code.
LCD Message
"The phone number or extension is not valid"
Corrective Actions
1 Make sure you entered the phone number / PIN code correctly.
2 Make sure you have the correct PIN code; it may have changed in the Enterprise's
Active Directory.
3 Make sure you used the PIN code sign-in method (Sign-in softkey > Switch sign-in
method > OK hard key or Select softkey).
8.3 IP Phone Fails Registration Process
Problem
The phone fails to register.
LCD Message
-
Corrective Actions
Make sure:
1 DHCP Option 43 has been configured.
2 Access is possible from the following Web site:
https://YOUR_AUTHORITY_SERVER:443/CertProv/CertProvisioningService.svc
3 If the environment supports more than one CA Certificate, this must be included in the
CA Certificate file and loaded to the IP phone.