HELP! I'm getting a "406 Not Acceptable" message

Hi Zicky, 

I just wanted to post our findings on this to date in case anyone has a similar problem (I've changed the domains in the URL) - reposting: 

The issue is that the web host has some security mechanisms in place that attempt to block malicious urls.  The problem is that these security mechanisms are generating "false positives", just like when you get a valid email in your spam filter.  

So many URLs that contains "http://" get rejected.  This is a problem because it prevents you from entering the URL of some of your social media sites into your CMS because when those forms get submitted to the CMS via either GET or POST submissions they get blocked for containing a "http://" value that matches a securityfilter even though they are perfectly normal urls.

Adding ?address=http%3A%2F%2F to ANY url on the site demonstrates the problem, here's an example:http://example.com/?address=http%3A%2F%2F

The server returns this response to the above url: 

Not Acceptable
An appropriate representation of the requested resource / could not be found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

But you'll note that changing http:// to abcd:// allows the site to function as normal:http://example.com/?address=abcd%3A%2F%2F

Can you forward this email to your web host, ask them what security filters they have in place and if they can disable or update them so they don't get triggered when we submit a form that contains "http://" in the value?

Let me know what they say, thanks!