shows different message in windows and linux server

shows different message in windows and linux server

I am using
<a href=" <?=base_url();
?>index.php/admins/candidate/inactive/<?=$list['candidateid']; ?>"
onclick="return confirm('Are you sure you want to inactive this candidate
?');"><img src='/images/inactive.png'> </a>
for the delete/inactivate confirmation message in my project.
When I run in my local system I see below message when I click on
inactivate link.
and when I deploy the application to linux production server, I get below
message. please see below image.
but here in production server, it shows "The page at www.xyz.xom says: ".
Why it is that?
Please help, I want to show only message, not the above "The page at..."
text.
Please suggest the solution.