Step 1: Download Zoiper softphone app(free) from below url.
Step 2: Install Zoiper client on your Windows PC/Laptop.
Step 3: Once launch the Zoiper app first time, You need to allow windows firewall
Step 4: Configuring Calncall SIP Trunk
Go to Settings –> Configure a new account and select “SIP”
Step 5: Enter the SIP account Credentials(will be provided by us)
Step 6: To check the registration status and settings
Go to Settings –> Preferences