saving to .txt trouble

I have created a flash login that loads a .txt file with the password inside. This works fine but i created a registration page that when the user types a username in the app it creates a directory called (what the user called the username) and then a file called password thaat includes: password=(password). The problem im having is that when i tested this it returned an error, can anybody go through my scripts and tell me what im doing wrong.

Thanks for any help