It only seems to happen to the home page and I can fix it by clearing the cache for the home page (I don’t have to clear the whole cache).
This doesn’t happen immediately after any changes to the site, it could be hours later that this happens.
Any ideas what might be causing it? Because of the url it’s redirected to it looks like it could be a Cloudflare problem.
The problem happens on all devices and browsers (Windows Firefox & Chrome and Android phone Chrome so I don’t believe it’s browser related. The link to the home page hangs for a second and then redirects to the 404 page.
The wsidchk= query string is added by a firewall product called Immunify360 / Webshield, which many hosting providers use to protect their servers. Talk to your hosting provider to see if they will let you adjust the sensibility or somehow adjust this firewall.
If not possible, for as long as you are using a hosting provider with some firewall that intercepts requests, you need to either a) not use a Cache Everything page rule, or b) reduce the time in the Edge and Browser TTL settings in your Cache Everything page rule, so that when/if that firewall page is cached, it won’t last long.
Thank you very much for that knowledge, I was totally lost as to what was causing the problem.
Hopefully if I reduce the time in the cache settings that will fix it. At least I am now armed with a likely solution.
Your help is much appreciated.