Isolate reason a phone device is unreachable


If a babelforce call fails to get a response from an agent phone device, we will label this outcome as "unreachable".
This can be caused by the traffic not always getting through the router, the firewall at router, the firewall on the computer/device that the softphone is installed on, the softphone being frozen, the operating system on the computer/device not responding, a loss of internet connection (even briefly) and a few other reasons also.
When this happens we mark "unreachable" in the call logs. We also show the agent that they were "unreachable" on the last attempt and we present a feedback message and a reset button. It will look like this:
If the agent resets then the unreachable status is set back, so that calls will try the agent again. If the problem was just intermittent, e.g. device did not respond, or brief break in connection to router, etc. then after the agent presses reset, it would work again on the next call.
If the issue persists, you can begin to isolate the source of the problem as follows.
To troubleshoot - go through the steps here and do a test after each case
First verify again that the issue occurs: 
0a. do test call that is routed to the agent and verify that you get the issue "unreachable"
0b. call the softphone directly using the babelforce SIP ID 999xxxxxxx number from another phone/softphone connected to another babelforce SIP account.
These will verify that the issue is currently reliably presenting itself.
Next, make one change at a time to the route and isolate: 
Do each of these changes and test inbound call after each step. 
Note that it is vital to try to test just one change at a time.
  1. restart the softphone
  2. restart the computer/device (if you have softphone on a computer, turn off the firewall on the computer for a test)
  3. connect to a different network, e.g. switch from one wifi network to another, switch to LTE/modile data with no wifi, switch to wired connection
  4. restart router
If you go through the steps in order and the test with a call each time, then you will get closer to isolating WHERE the issue could be that causes the softphone not to be reachable. If you locate a change where observed behavior switches from "unreachable" and starts working, then you might be on to something.
Try to reverse the change and repeat to isolate reliably
Now if it is technically possible for the particular change, reverse the step again and verify that the issue reoccurs. For example, if it is a switch from LAN to LTE, switching back would most likely reliably cause a reoccurrence. That is, of course, one of the easy cases. If you have one of those, then you are probably closing in on the target.
Moving to remedies
After doing that, you could look at how to improve the end-to-end route to solve the issue. The remedy will depend on the isolated issue.
For example the rules in the firewall, the network traversal method used. Or other action if the problem occurs at a different part of the route.
Our section on Technical Network Requirements has more detailed information on how things should be set up in your network for high quality voice calls.
If you have issues isolating the problem with the steps above or if you cannot find a remedy, then please contact us at
For us to investigate, we will most likely need the detailed outcomes of the above tests.
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