Known Issues/Resolution in Spark 2.6.0

Some open issues and known resolutions (if around)


  • Missing Phone button. Resolution: This is caused by a missing STUN server to help the start of the phone connection. If you want to use this feauture you can activate it in Openfire and add the property “stunFallbackHost” to the file You can add your Openfire server or some external stun server like “” which used to be a hard coded default in Spark.
  • File transfer does not work.
    Resolution: Fixed in nightly build 354
  • Mac Version: Look and Feel is not native.
    Resolution: Use the Preference Menue to Switch Appreance to “Max OS X”. This resolved this issue. There will be a hot fix release for Mac to adress this issue.
  • Mac Version: Sound does not work.
    Resolution: Make sure that Spark is executed in 32 bit mode.
  • Broadcast window too large: The new broadcast window does not handle large text well. A fix is planed. Workaround: Keep your broadcast text small. Is fixed in nightly and will be included in 2.6.1.
  • Copy & Paste does not work. Resolution: This may be related to the spellchecker. Please try copy/paste with disabled spellchecker.
  • Spark will not start on Windows 7 64bit. Resolution: Java applications have issues with ClearType ®. Try to disable Cleartype.

The development path for 2.6.1 is available here: Open Issue List


Could you tell me how to activate the STUN server in Openfire 3.7.0 ?


Openfire -> Launch Admin -> Server -> Media Settings -> STUN Settings.

Local Server Enabled [x]

You need to select two different IP’s to let Openfire act as a STUN Server.

You can also set up external STUN servers on the Openfire server, if you don’t have two IP’s.

But how to set up a STUN server? Where to download a STUN server software?

Michael, you do not have to. You have three options:

-Give your Openfire Server two IP Adresses and Openfire works as STUN server, if configured

  • Use a public STUN server via the Openfire configuration, eg “

  • Change the config of all Spark clients in your environment to like the first bullet point describes it.

Is the stunFallbackHost workaround working for everybody?

I’ve tested setting up the fallback host to my openfire server where I have two ip addresses on the same LAN and with the integrated STUN server enabled.

Testing 2.6.0 on 4 windows systems I get the call button seldomly, and haven’t been able yet to make a call.

I supposed it’s related but some stuff is written to the console about ICE.

Added known problems:

some machines spark cannot send/receieve file transfer (crash) and nightly builds not solve the problems (I paste it two logs entry and no answer). some machines contact list double click and sparh crash and nightly builds not resolve the problem.

We can not reproduce both issues reported by KKimber.