I am writing a login page for my web application, and i want to implement error messages for when incorrect login details are submitted. I have so far created code which will give an error if an incorrect password is entered, when an incorrect username is entered, or when the username and password fields are left empty, my problem is giving an error message when an incorrect username and password combination are entered. I have tried everything i can think of, but keep getting an "internal server error". The code i am using is shown below 
  }
# Display error if username or password fields are left blank 
if($user_name eq "" || $password eq "") {

         &error();

} else {

#check if the user name and password are in the database
$sth = $db->prepare(q{SELECT user_id, password from user where user_id
+ = ?})
$sth->execute($user_name)
                
while(@row  = $sth->fetchrow_array){

         if($user_name eq $row[0] && $password eq $row[1])
         {
                   #go to main page
         } else {
# If the username or password are not in the database                 
+                                                      if($user_name n
+e $row[0] || $password ne $row[1])                                   
+     {

                  &error();
}

[download]
Can anybody see why this code isn't working? I would greatly appreciate any help you can give. Thanks

In reply to login page by Anonymous Monk

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