In contrast to TAPI lines, the Set call forwarding function is not available for SIP lines for the use of softphone functions (SIP) when connecting third-party SIP terminals or must be set on the terminal via Feature-Code.

Version note June 2019

As of ProCall 6 Enterprise version 6.2, call forwarding for SIP lines can be performed by the UCServer.

ProCall Enterprisefrom version 6.2
Telephone system


Set call forwarding by user

The UCServer supports the following call forwarding for the telephone systems released by estos:

  • Forward all calls
  • Forward all internal calls
  • Forward all external calls

Call forwarding on busy:

  • Forward all calls
  • Forward all internal calls
  • Forward all external calls

Several call forwardings can be set up at the same time.

Set call forwarding on UCServer

Not all PBXs support fixed call forwarding for disconnected subscribers on third-party SIP lines.

When using call forwarding in the UCServer, please note the following:

  • No information about call forwarding is sent to the telephone system.
  • In order to use the UCServer call forwarding function, the SIP lines must be set up for the second call.
  • A call forwarding set up in the telephone system for all calls or on busy is executed before the call is signaled at the UCServer and is therefore always valid.
  • Call forwarding is performed by the PBX via SIP status code 302, if supported by the PBX.

Call forwarding on the UCServer

As of ProCall version 6.3, an "Administrative call forwarding" valid for all users can be set up by the UCServer in the properties of the SIP line group on the estos UCServer.

If a phone number is entered in the User settings under Phone numbers – Mailbox, all incoming calls are forwarded to this extension if the user is not logged in with an estos client.

Version note

Since estos has no influence on the further development of the supported telephone systems by the manufacturer, we cannot guarantee that the instructions described above will also be fully valid for future releases.