Hi Holger,

One possibility is that the requested Java memory size is too big. Try this:

1. use a text editor to open the file ".tracker.prefs" located in your use home folder (C:\Users\Doug on my Windows 7 machine)

2. If you find a line like "<property name="memory_size" type="int">1000</property> then change the number to something smaller like 256.

3. Save this and see if Tracker will launch. If it doesn't (or if there is no memory_size property) then please let me know.

Hope this helps. Doug

Hi Doug,

Thanks for your quick answer. Unfortunately the file ".tracker.prefs" doesn't contain the line you have mentioned.
This is the content of the file:


<object class="org.opensourcephysics.cabrillo.tracker.Tracker$Preferences">
    D:\Users\Xeal\Videos
</object>

I hope you can help me :)

Holger, I still think it could be related to the maximum Java memory size being too large. So here's another thing to try (thanks to Tom Letkewicz). This limits the maximum memory to 256MB.

• Open the Control Panel and search for "environment"
• Click on "Edit the system environment variables"
• Cllick on the Environment Variables button
• In System Variables, click Add
• New Variable Name: _JAVA_OPTIONS
• New Variable Value: -Xmx256M
• Click OK

Then see if Tracker will start. Doug

Hi Holger,

Please email me directly at dobrown@cabrillo.edu and I can send you a small test jar so you can confirm that your Java installation is working. Thanks!

Doug

The Problem is solved.

For some reason I've deleted QuickTime. After I've looked what Tracker told me at the Help|QuickTime items, it mentioned that QuickTime could not be found. I thought it would be a good idea to install quickTime again - and Tracker works fine now.

By the way: Version 4.00 worked without QuickTime also.

Thanks a lot to Doug and his uncomplicated support.