Error: "undefined external error" (after Windows 10 update 1803)
Fix: Adjust microphone permissions in Windows Settings:
- Navigate to Windows Settings => Privacy => Microphone.
- Ensure that microphone access is allowed for the Vantact Softphone Lite app.
Error: "Unable to find default audio device"
Fix: Ensure your system has both speakers and microphones connected and configured as default audio devices. This is necessary for making calls and using RDP connections.
Error: "An invalid parameter was passed to a system function"
Fix: Grant microphone access in Kaspersky Anti-virus settings if applicable.
Error: "End of file"
Fix: Change the Transport setting from Auto to UDP in the Vantact Softphone Lite settings.
Can't make or end a call
Fixes:
- Verify SIP account configuration: Check fields such as domain, username, password, proxy, server, login, and transport.
- Ensure correct dialing format and number.
- Disable SIP ALG (Application Layer Gateway) in the router settings.
- Test with a clean installation of Vantact Softphone Lite, disabling additional features by default.
- Try adjusting settings such as "Allow IP rewrite" and using/not using STUN server.
- Set the source port in settings to 5060 if necessary.
- Test calls from another computer or different internet connection to isolate the issue.
- Review PBX configuration for NAT (Network Address Translation) support.
No sound or one-directional sound
Fix: This issue can occur due to NAT traversal problems with routers:
- Check if your router has SIP ALG enabled and disable it.
- Refer to your router's Knowledgebase for specific instructions on disabling SIP ALG.