CAPTCHA not displaying within an internal network

Question

I have a site that contains simple captchas for a contact form and registration form. The captchas have and continue to function fine on all networks except for the internal network of the client who owns the site. I am at a bit of a loss for what could be causing this issue.

Could the issue be with the firewall? I don't see how the firewall would be blocking anything external since I don't think the captchas rely on external resources? I could be wrong about that.

The only clue I have is that the issue began after the site was migrated to another server. Any help with this would be greatly appreciated.

Using v2.3.1

<tr>
    <td>
       Submit the word below:<br />
       {captcha}
    </td>
    <td>
       <input type="text" name="captcha" />
    </td>
</tr>

Answer 1

Quick check - if the captcha is not displaying, and they can still submit the form... then the chances are they are logged into the backend of the EE control panel and their member group has captchas disabled.

If the captcha is not displaying, and they cannot submit the form due to captcha non entry. Then i would first suggest looking at the path for the captcha - does it use a reference different than the site, a domain that is perhaps blocked? Companies often do funny things with their own domain inhouse which could cause this kind of issue.

if not i think most people will need a lot more details. like output, online links and examples. is it definitely working, or is one or other having cache issues, etc.