title: Troubleshooting Access Violation at Address. Read of Address 00000000
body: <p>The same version of Delphi 7 Code has been deployed at computers throughout our organization. </p>
  
  <p>Each time user A accesses record Z on computer F1, the following error is displayed:</p>
  
  <pre><code>Access violation at address 00642E83 in module 'foo.exe'. Read of address 00000000
  </code></pre>
  
  <p>I've followed the same steps on my own computer with my user, and on another computer with another person's user, and have been unable to replicate it (and hence, can't debug...). </p>
  
  <p><strong>Additional Info as requested</strong> (not sure how helpful this will be)</p>
  
  <ul>
  <li>Record Z is a row in an Interbase DB holding contact and call history of people who have called in.</li>
  <li>All the computers in our org use the same build of Windows 7.</li>
  </ul>
  
  <p>So when... </p>
  
  <ul>
  <li>User B accesses record Z on computer F2 there is no error.</li>
  <li>User C accesses record Z on computer F3 there is no error.</li>
  <li>User A accesses record Z on computer F4 there is no error.</li>
  <li>User A accesses record Z on computer F1 (after reboot) there is the same error at the same addresses mentioned.</li>
  </ul>
  
  <p>It appears that computer F1 is the culprit.
  However, at this point, I'm not sure how to troubleshoot further.</p>
  
  <p>Any suggestions?</p>