Spark freezes when I click on user's name to open chat window

Hi all,

First post, and only been using Spark for a few months now.

Whenever I open Spark, and then click on a user’s name to open a chat window with them, Spark freezes up and never opens the window. I have the log files if anyone needs them, but I am not sure if it is ok to post them here or not.

Potentially important info:

-Windows 7 Home Premium SP1 64-bit, with all current updates

-AMD Phenom II P650


-Office 2010, Firefox 10.0.1

-I am using this at work

I would really appreciate any suggestions.




does it use 25% (1 core, I assume that you have a 4 core CPU) CPU or it the CPU idle?

Spark JVM Settings describes how to set JVM options, enabling the GC log will likely not help but as soon you have it you can set other parameters:

-DsuppressSwingDropSupport=true (drag and drop may stop working)

One of these: -Dsun.java2d.ddoffscreen=false -Dsun.java2d.d3d=false -Dsun.java2d.noddraw=true

Hopefully one of these helps.

Look also at the GC log file, it must not show Full GCs every 3 seconds.


UPDATE: I found this thread ( which I think solved the problem I was having. Spark was only freezing when I tried to open a chat window with a specific user. However, now I have a whole new problem that did not happen before.

I deleted the specific user transcripts as instructed in the above-mentioned thread. And now Spark has difficulty logging me in, and when it does, it does not stay connected for more than a few seconds. How would deleting transcripts with a specific user affect logging in?

What can I do to solve this problem?

Agtain, TIA,


Hi LG,

Thanks for your help. Do your suggestions above still apply considering the update I posted just after you posted this?


You should see errors in the log file if the connection is not stable. Anyhow it may be hard to debug.

The JVM settings do only help if Spark crashes, I don’t think that your client has a memory problem.


looks like you have a corrupt profile of Spark. A standard procedure for repair is the deletion of the profiles folder and a fresh install of Spark. I hope you are using Spark 2.6.3, which is a stable edition.

Procedure (paths may vary, I have a German OS, hence guessing the English ones):

  • Uninstall Sparl via system control. Check if there is anything left in c:\program files\spark and delet that manually.
  • Open c:\documents and settings\\application data\spark
  • delete everythink in there
  • open c:\documents and settings\\spark (if it exists due to an older version than 2.6.3)
  • delete the content
  • reinstall Spark

Prior doing this:

Check that you know your password

Note the server settings in the login dialog

You will loose all chat history by following this procedure

Reinstall Spark and configure

Let’s hear how that worked for you.


I have a same problem with users…

Unfortunately spark 2.6.x series problamatic version.

Use it 2.5.8