Unable to create new instances of wwwForm

Hello Everybody,

i have a big Problem.
I want to check an given Login via www and wwwForm. I have an php script on an server and i wanted to check the Username and Password. I’m using Unity3d 3.5.
my code looks like this

IEnumerator CheckUser() {

string URL = "www.mydomain.com/checkuser.php";
WWWForm form = new WWWForm();

form.AddField("myForm_userName", username);
form.AddField("myForm_Password", Password);

WWW w = new WWW(URL ,form );

yield return w;

.......

}

the problem is that sometimes it works but sometimes it hangs on this command:

WWWForm form = new WWWForm();

nothing happens. It is not work over that

what could it be ?
It is a Webplayerapplication

Regards
Chris

Did anybody have the same problem ?

Debug what your getting back from the webserver then maybe you will find out why it’s not working :
WWW.error

Thank you for your answer. The problem is not that the Url or something is wrong it works sometimes. The Problem ist that this command

is not working. by calling this the Programm hangs and is not coming back. There is happen nothing. The Programm stands.