Somehow the $sth->execute seems to have gotten skipped.

Change the following 

my $sth = $dbh->prepare("SELECT * FROM $users_table WHERE username = '
+$username' AND user_password = '$userpass'");
        $sth->execute;

[download]
to 
my $sth = $dbh->prepare("SELECT * FROM $users_table WHERE username = ?
+ AND user_password = ?");
        $sth->execute($username,$userpass) or die $dbh->errstr;

[download]
It is a more secure way of doing things (protects against arbitrary SQL code injection attacks -- has nothing to do with your present problem)

The only reason I can see why your script sometimes runs and sometimes doesn't run is in a combination of inputs which skips the execute code. Are you sure all the if ... then ... else ...-logic is OK?

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

In reply to Re^5: Premature end of script headers issue by CountZero
in thread Premature end of script headers issue by Anonymous Monk

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