Why Can’t I Transfer Calls?

What happens if you can not get calls transferred to an extension or internal number?

Usually, a hardware or network problem is the reason why the call transfer function stops functioning. It is important to determine if only one device or multiple devices are experiencing the issue. The problem is probably hardware-related if it only affects one device or a single location (in the case of multiple sites)

Helpful Tips:
  • Lets reboot the router. It's easy and quick to do and allows us to rule out any router issues first.
  • Are you following the correct transfer procedure?
  • Does each Device (Phone) have a unique port. E.g. extension 201 uses port 6071, extension 202 port 6072 etc.

If you are experiencing call transfer failures on one single device

  • Check that the physical connections (e.g. cords, Ethernet cables, etc.) are correctly connected.
  • Test the connections with another device. Replace any connections deemed defective.
  • Plug the non-working device into a location where there is a working device.
  • Try a working phone in the same area where there is a non-working device.

If experiencing call transfer failures on multiple devices and different sites:

  • Each device (phone) must use a unique port. E.g. extension 201 uses port 6071, extension 202 port 6072 etc.
  • Verify the Internet connection is working correctly for all devices connected to the network.
  • If there is more than one router on the network, check for Double NAT. For information on Double NAT troubleshooting, click here.
  • Check the internet router for a setting called SIP ALG, which can affect VoIP traffic while not affecting computer traffic. For information about SIP ALG, click here.
  • Call the local Internet Service Provider (ISP) to ensure that the network can handle VoIP traffic.

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Still, want to speak to a colleague?

Can't quite figure it out or get it right? Call our Customer Happiness Team at 021 012 5000 or send an email to info@voys.co.za