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ProM Lite error


Everytime I launch ProM Lite, I get the error "An error occurred while starting the application" with the popup name Launch4j. I uninstalled and reinstalled but still does not work.

How do I resolve this?

Indrajit(Jit) Datta Chaudhuri
Senior Consultant - BPM
Leonardo Consulting
Perth, Australia


  • hverbeekhverbeek Posts: 735
    Dear Jit,

    To resolve this, please follow the following steps. An explanation why this may happen follows after that.

    1. Open the WIndows registry editor (sorry about that, but better be safe than sorry), and remove the "impl" folder form the "Computer\HKEY_CURRENT_USER\Software\JavaSoft\Prefs\org\processmining\framework\plugin" folder.
    2. Start Prom Lite using the ProMLite.bat file, which is located in the folder where you have installed ProM.
    3. Wait for ProM Lite to start up. This may take a couple of minutes. While starting up, ProM Lite may show all kinds of messages, including exceptions. These can typically be ignored.
    4. When started up, close ProM Lite, and start it again from the Start Menu (like you did before). After some seconds (not minutes), ProM Lite should be up and running.

    The problem is caused by the maiden run of ProM Lite, which requires more time than subsequent runs. The Launch4j wrapper has a timeout set at two minutes, and if ProM Lite is not up and running at that time, the wrapper concludes that an error has occurred. Apparently, in your case, the maiden run requires more than two minutes.

    During a maiden run, ProM Lite checks all jar files for ProM plug-ins. For this, it tries to load and scan all jar files. The excpetions you may get are typically related to non-ProM jar files that ProM is trying to load for the plug-in scan. If ProM Lite find proM plug-ins in a jar file, this information is stored in the Windows registry, in the folder as mentioned above. As a result, in a subsequent run, ProM lIte does not need to scan a jar file, as the information it needs can be retrieved from the registry. This explains why a subsequent run starts much quicker than a maiden run.

    In you case, the maiden run took too long, that is, more than two minutes. As a result, the registry may contain erroneous information. This explains why we need step 1. The two-minutes timeout is not present when starting ProM Lite from the bat file, this explains step 2.

    Kind regards,


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