Hi Daniel,
When you say that the log file wasn't created, are you referring to the orbeon.log? By default that file gets created in ../logs/orbeon.log, which means that if you start Tomcat in tomcat/bin, you'll find it in tomcat/logs, along the other log files. If you can't find it there, I'd recommend you set an absolute path in Orbeon Forms WEB-INF/resources/config/log4j.xml to a place where you want the orbeon.log to be.
Once you have that taken of, you'll be in a much better place to solve the problem you're after, as the log file will most likely contain some indication of why that process is failing.
Alex
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