One of my favorite websites: http://jessiejofficial.com (yes, I'm a Jessie J Fan :')) has recently started displaying the error message "412 Precondition Failed" whenever I visit it from my home network, even when I use Tor Browser.

At first I thought that this was an issue with the whole website, however I have contacted the web developer and he has said that they has been plenty of hits within the last 48 hours. Plus, I discovered tonight that I can access the website from my phone, through the mobile network.

So it appears to just be my network as all of the devices in my house connected to the WiFi display the same error when I try to visit any page of the site. However there have been no changes that we are aware of or are noticeable to our network since the website was accessible, and I have just heard that another person in a different part of the country is experiencing the same difficulties also.

Any help/advice/suggestions would be appreciated greatly

Update: When trying to ping 'jessiejofficial.com' in Windows command prompt the request times out on all four attempts, on any computer connected to the wireless network. I can now also confirm that the same thing occurs on my MacBook Pro.