1. Download MicroSIP here and install it.
2. Right mouse click on "MicroSIP" icon, as shown below and select "Add account".
3. Enter the following settings and click "Save".
SIP server: sip.zadarma.com
User: Your SIP number (for example 111111) from your personal account
Domain: sip.zadarma.com
Login: Your SIP number (for example 111111) from personal account
Password: Your sip number password from your personal account
Your name: Your SIP number (for example 111111) from your personal account
SIP server: pbx.zadarma.com
User: Your PBX extension number (for example 1234-100) from your personal account
Domain: pbx.zadarma.com
Login: Your PBX extension number (for example 1234-100) from your personal account
Password: Your PBX extension number password from your personal account
Your name: Your PBX extension number (for example 1234-100) from your personal account
4. If the settings are correct, the status will appear as "Online".