Hi. I had the same problem and I solved it. In my case, I had a stand-alone application (EXE file) to distribute to several target computers. In some of the target computers, when I ran the EXE, I received the "fl:filesystem:InvalidArgument" error.
Eventually, I found the problem: If the EXE was located in a path that included Hebrew characters (I'm from Israel) it gave the error.
To solve it, I simply renamed all folders in the path to Latin characters and it worked like magic :) Hope this helps...
