If you experience a crash please do the following:
Delete the .ini file
Close Har-Bal and delete the HarBal.ini file which lives in the folder,
C:\Users\{your user name}\AppData\Local\Har-Bal\Har-Bal 3.0
If you are on a Mac, follow the path below
Try going to the folder {your user name}/Application Support/Har-Bal/Har-Bal 3.0 and delete the file HarBal.ini.
The file may be hidden. If so, open your explorer window.
Click on Tools/Folder Options/View and place a checkmark in (Show Hidden Files and Folders)
It's a known bug that we will have a new download for soon. It happens if you have a reference open and you close the session and then try and open a new one. If you always close the reference before closing Har-Bal it should not crash.