To use Viber on your PC, you must have an on a mobile device first. Download - Viber
For older systems, the official site provides a specific "Windows 8 and lower" link tailored for Windows 7 stability. Key Features for Desktop Users viber free download for pc windows 7 ultimate
Call any landline or mobile number worldwide at competitive rates. Installation & Setup Requirements To use Viber on your PC, you must
Your conversations remain private and secure with built-in encryption. To use Viber on your PC
All your chats, contacts, and call history are automatically synchronized between your smartphone and PC.
Enjoy high-definition audio and video calls directly from your computer using your existing microphone and webcam.