i'm getting the above error upon launching the ide. here's what happens: click on icon to launch ide. nothing much happens for about a minute (though lots of disk activity), then an alert window pops up with the "Launch4j: An error occurred while starting the application." error message. about 15 seconds later the IDE window appears, and as far as i can tell everything work correctly thereafter.
the SECOND time i attempt this, the same thing happens EXCEPT far less disk activity. IDE is version 0021, java is the latest release - have renamed the java directory in the IDE's directory to 'javaold'. os is XP SP3, running on an EM350 netbook (1gb ram).
reading other people's comments, this seems to be a serial port issue, caused by the IDE attempting to locate every serial port. under windows this is a 'dodgy' business at the best of times - so many different underlaying hardware options. even under msdos it was a pain.
since this seems to be an extremely common problem, may i suggest the following solution: change the IDE so that there is an option to NOT try to enumerate all the serial ports by default, instead allow the user to enter the name of the serial port as a simple text string. then the IDE can validate that an arduino board is attached to the name entered.
any other solution will almost certainly work on some PCs, but NOT on others.
cheers, rob :-)