Sip Phones connection issues

In case your SIP phone connection hasn't been successful, please check the following:
  • Possibility to add long server address. When you connect sip phone in user phone preferences page, you need to add 38-symbols server address. If your sip phone does not allow to add min. 38-symbols server address, you won't be able to connect this sip phone.
  • It is preferable to use Sip phone with it's default settings during connection. Several sip phones may not be working if their default settings have been changed.
  • It is preferable to have the last update installed on your Sip phones. Some sip phones may not be working because they haven't been updated. 
  • Your Sip phone should support either  TCP or UDP protocol, as server is using only these protocols. If your Sip phone supports both protocols, then UDP is preferable. 
  • Make sure you have STUN-server disabled in your Sip phone, as it may cause problems with traffic going through NAT (it results in conversation interruption\call break when the call is made). 
  • Make sure you have SIP - ALG option disabled in your office internet router settings. If the option is active it may result in conversation interruption\call break). 
If you use SIP phones, you need to know that call cannot be forwarded to more than 10 phones at the same time.
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