A better way to do this is: 
Submit.onRelease = function() {
dataHandler = new LoadVars();
dataHandler.onLoad = function(success) {
if (success) {
if (dataHandler.urlcheck != "http://www.avalon-rev.dk") {
_root.myTextBox.text = "file not found - error";
} else {
_root.myTextBox.text = dataHandler.urlcheck;
}
} else {
myTextBox.text = "Error Loading File...";
}
};
dataHandler.load("text.txt");
};
Put this code in ur _root timeline.
Tell me how it goes,
yours,
h88