Thanks for all the comments. I have considered each of them. I don't think i have access to the server logs for the server i am working on, so i can't check the exact perl error when i get an internal server error. Where should these logs be? When i applied jberts first example example all cases work fine except when an incorrect username and password are entered. In that case i get an internal server error. 
if($username eq $row[0] && $hashPassword eq $row[1]) {
     # Go to the new page
  }
  else {
    error();
  }

[download]
Using the second example i am given access to the next page with the correct user name and an incorrect password. Does anyone know why this is happening?

In reply to Re^2: elsif loop by Anonymous Monk
in thread elsif loop by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.