KMWitt

We think we can rule out the web hosts as the sites are on different ISPs.

Also, we are behind Windows Small Business Server 2011 but we can’t see anything that might be interfering.

A) IE 11.0.9600.17351 Desktop
B) Windows 8.1 Pro

What makes this issue hard to track down is that (most of the time) if you refresh the page one or more times, the page will eventually display.

Are you using IE11 on Windows 8.1?

The issue is consistent in that it always occurs on those sites, but random on when and which page it will occur on.

I couldn’t see anything strange in the access log. The error log showed multiples of the following errors from different IP addresses:

• Premature end of script headers: php-cgi
• client denied by server configuration:
• File does not exist: – most of these appear to be attempts to access wp-login.php at a location it doesn’t exist.

While the conditional tests are in the code, I’m not loading anything specific for IE11.

The pages it occurs on are random.

The sites it happens on are:
https://www.forteachersforstudents.com.au/site/
https://www.myteachershop.com.au
https://www.organicschools.com.au/

As a temporary fix to get rid of the error message, at line 150 I added the test:

if(!empty($domain['domain']) || !empty($out))

before:

if ( strpos( $original_url, $domain['domain'] . $out ) !== false ) {
    $type = 'internal-as-outbound';
}

I don’t know if this code breaks the ‘internal-as-outbound’ setting as I’m not using this function on my website. So far, it hasn’t broken anything else for me (yet…).