switch ($_FILES['Filedata']['error']) {  
    case 0:  
        $msg = "No Error";   
        
break;  
    case 1:  
        $msg = "The file is bigger than this PHP installation allows";  
        break;  
    case 2:  
        $msg = "The file is bigger than this form allows";  
        break;  
    case 3:  
        $msg = "Only part of the file was uploaded";  
        break;  
    case 4:  
        $msg = "No file was uploaded";  
        break;  
    case 6:  
        $msg = "Missing a temporary folder";  
        break;  
    case 7:  
        $msg = "Failed to write file to disk";  
        break;  
    case 8:  
        $msg = "File upload stopped by extension";  
        break;  
    default:  
        $msg = "unknown error ".$_FILES['Filedata']['error'];  
        break;  
}  
echo ($msg) ? "Error: ".$_FILES['Filedata']['error']." Error Info: ".$msg : "1";  
//1  This is 
required for onComplete to fire on Mac OSX