I've researched this up the wazoo but to no avail. I have a page internally that requires TLS 1.1 or 1.2. If they're not on, you get an error:
This page can’t be displayed
Turn on TLS 1.0, TLS 1.1, and TLS 1.2 in Advanced settings and try
connecting to https://SITEADDRESS again. If this error
persists, it is possible that this site uses an unsupported protocol
or cipher suite such as RC4 (link for the details), which is not
considered secure. Please contact your site administrator.
<?php
$contents = file_get_contents('https://SITEADDRESS');
echo "<pre>";
var_dump($contents);
echo "</pre>";
?>
It appears you're mixing server-side and client-side.
I assume PHP is running server-side, and it definitely will not be affected by IE's (which I'm assuming is running client-side) choice of ciphers.
If that doesn't make sense, let me know and I'll give further utterance...
If I'm understanding correctly, you want your own logic running on the client (IE) to detect if the client (IE) can reach the URL.
You could try firing an asynchronous request via Javascript (e.g. https://api.jquery.com/jquery.get/ )
YMMV, I'm not sure if IE will pass the TLS error into your Javascript code or not. Assuming it does, you should be able to at least handle any error events (arising from the Javascript HTTP request) and assume the client should not try to proceed.