Troubleshooting iSoftPhone issues

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Quick Setup Guide (DE/EN)

iSoftPhone Fritxbox guides

Download user guides here:

Configure iSoftPhone for iPad

Mit Asterisk gibt es zwei Möglichkeiten:
  • verwenden Sie das UDP-Protokoll.
  • Aktivieren Sie TCP-Unterstützung auf dem Asterisk-Server.

With Asterisk there are two options:
  • use the UDP protocol.
  • enable TCP support on the Asterisk server.

Issue: Call Disconnect in background.


iOS 6 does not support background mode with UDP.
Please try connecting to the server with the Transport-Type = TCP.

Cannot connect

The most common source of connection problems is when the firewall/router is blocking ports needed to communicate.

Please ensure the following ports are not blocked on the firewall:
  • Port 5060 for TCP/IP and UDP
  • Port 5070 for TCP/IP and UDP.

Listen RTP Port:
  • Port 10500 for TCP/IP and UDP.

Please also try values from range: 1025-65000 or ask your network administrator what port you should use.

Outgoing voice, can't make calls.

The codec being automatically sent to the server is not supported by the server.
It is recommended to manually select the codec, for example PCMU.

Port 5060 is being used by another device:

Go to Preferences/My Sip Account.
Set the Local Sip Port to zero or set a specific value allowed on your firewall/router.
Setting the port to zero will force iSoftPhone to look for an available port.

Error SIP/2.0 401 Unauthorized.

Check if you provider uses a Proxy server.
Go to Preferences/My Sip Account.
Set the proxy server in Sip Proxy.

Remove the application and trying installing the latest update.

Download the latest update from:

For Connection problems please follow this link:

Also review the Configuration Guide to ensure the account is configured correctly.

One Way Voice Issue:

In System Preferences/Security, go to the Firewall and add iSoftPhone to allow traffic.
You may also test with the firewall temporarily turned off.

In iSoftPhone/Preferences/My sip account
Set the Listen RTP Port = 0

Try using a STUN server

In advanced settings:
Use the Default button and restart.

Note for users with BBox2:

Belgacom has blocked the 5060 ports.
The workaround is
  1. to go to
  2. advanced settings > telephone > general
  3. there, you can replace all the 5060 ports by 49060
  4. for example enter the server address of your provider and clicked "apply"

Send us log files:

To help troubleshoot the problem, please send us the following:
  • Screenshot of Preferences/My Sip Account - we will check the settings
  • Create a screenshot using Applications/Utilities/Grab.

Sip Trace Log from the application Help menu- copy to text file and send to us.

Trace log

Open the Sip Trace Log from the application Help menu, copy to a text file and send to us.

Console Dump:
  • open Console (Applications/Utilities)
  • clear the console
  • try to launch iSoftPhone
  • copy and paste Console to a text file and email to us.

Crash Log

Please let us know if it resolves the issue for you.
If the problem persists please send us the crash log which can be found in

~/Library/Logs/DiagnosticReports/     where ~ means user's home folder.

Troubleshooting form

Contact Name:
E-mail address*:
Your iSoftPhone version & build level* (see "About"):
Your OSX version:
Describe your problem*:
Send us log/trace/crash file(s):

* - required

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