Http 408/409 Server Busy – Internet Explorer not showing Web Page – Working Fine on Chrome/Mozilla

I am trying to access one of my Website Page

https://<site-url.com>/contact-us/ 

This works fine on Chrome and Mozilla, and I am able to see the webpage loaded om respective browsers.

However, it throws error when trying to access from Internet Explorer (IE11):

HTTP 408/409 Server Busy 

I am puzzled on how this could be possible. Online Resources suggest that this error occurs when there are too many users accessing the page. However, this is a newly deployed website where the only user is me, and the page only contains a contact form, so it is in-fact the fastest loading page on my site.

There are other interesting occurences:

  1. I can access the page from my XAMPP Localhost on IE11 without any issue.
  2. If I move my page to literally any other url like https://<site-url.com>/reach-us/ instead, then IE11 displays the page without throwing above error.
  3. If I try to access a non-existent url: https://<site-url.com>/contact/ , then also I am shown the HTTP 408/409 error instead of a HTTP 404 error. Now, if I try https://<site-url.com>/contac/, then I am shown HTTP 404 as expected. (is the keyword “contact” in the url causing the issue? What even!)

Here is my .htaccess file where I have written rewrite rules for applying https:// to the url and removing .html extenstion from the urls.

RewriteEngine On RewriteCond %{HTTPS} !=on RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]  RewriteCond %{REQUEST_FILENAME} !-d RewriteCond %{REQUEST_FILENAME} !-f RewriteRule ^([^\.]+)$   $  1.html [NC,L] 

Is this causing the issue by any chance? I think it is unlikely since this would have caused similar issues in other urls like .../about-us/ or .../reach-us/ etc.

My option here is to move my page to ./reach-us/ here, but I don’t want to since this is working fine on Chrome and Mozilla.

What I have deduced is that the keyword ‘contact’ in the URL is causing the issue, which is outrageous to assume since it is only occuring on IE and not on Chrome/Mozilla.

Any Inputs are greatly appreciated. I have hosted my site on bluehost.com