State of knowledge

August 2021


Automatic redialing on the ProCall client does not work, only 1 attempt is made although 5 are set. 

This emulated feature is only available for CTI and not for softphone functionality.

Possible reason

The telephony system does not return a direct busy (Busy), this interrupts automatic redialing.

Checking possible reasons

With the help of ePhone.exe it is possible to check what the telephony system returns when an outgoing call is returned to a busy number.

  1. Select the TAPI line that you want to test at Device and press the Start Session button. The TAPI line is opened and the button now says End Session.
  2. Type in the phone number that is busy at Phone #: and click Make Call.
  3. In CallState after "Dialing" for a short time a "Busy" does not appear immediately but another status e.g. "Ringback".


The telephony system must return a "Busy" directly after "Dialing".