Zoiper is not an officially supported softphone, any Zoiper support should go through their company. SMS services will not function with Zoiper.Configuring Zoiper consists of entering user information/credentials found within the PBX Portal, and this guide will continually reference information on this page to complete registration. The configuration steps within this guide can be used with FREE and PRO versions of Zoiper.Please note that this article is a continuation of our Generating SIP Credentials article.To ensure the device information/credentials are readily available, please first navigate to PBX Portal → Users → Edit User → Phones and select the 'Edit' button found to the far right of the device you wish to register.Once the user device information is available to you, launch Zoiper and sign in with the user credentials found on the 'Edit Phone' page.When asked to enter the Hostname, please enter the Domain/Proxy information found on the 'Edit Phone' page.Next, click the checkbox next to 'Optional' for Authentication and Outbound Proxy and then enter the Outbound Proxy information found on the 'Edit Phone' page. You may leave the 'Authentication username' field blank before clicking 'Next.'After entering the Outbound Proxy information, you will be prompted to test possible configurations. After initiating testing, you should see SIP TCP selected with a 'Found' indicator to the left of the success message.After the above steps are completed successfully, the selected device will show as registered in the PBX Portal User Devices, indicated by the green checkmark icon seen below.Disable STUNAfter completing the steps above, it is important to make sure the Global STUN function is disabled, which is typically enabled by default.To disable STUN, navigate to Zoiper Settings → Advanced and make sure the 'Use STUN' box is un-checked, as seen below. Configure Audio/Video DevicesOnce Zoiper has been configured, please remember to take the time to set up your Zoiper audio, microphone, and video device settings.Once you have selected/tested your preferred Audio Input/Output devices and video settings, the Zoiper configuration is now complete.