Are you on a Windows machine? If so, is your account that you are running icamsource under classified as an administrator account? What version of Windows?
If it is Windows, I think it has to do with icamsource not having permission to write files to the directory chosen for motion events. It seems like I ran into this issue once, after changing the motion event directory from the default to some "protected" folder, and had to add permissions to allow it to write to that directory. It would have been easier to change it back to the default folder...but I needed it changed for a reason. If you changed the motion event folder, you might try changing it back.