What does this error message mean?

When the plugin is preparing to request a scan it sends the naked domain name to a remote API service here [1] which then sends multiple HTTP requests to your website in order to search for signs of an infection. Sometimes people install their websites in certain way that the plugin cannot understand and decides to send a incorrect domain name which SiteCheck cannot reach, hence the message “404 Not Found”.

In your specific case, it seems that your website is not here [2] but here [3] so you have to go to the “API Service Communication” panel in the plugin’ settings page, scroll to the bottom and change the value for the option “Malware Scan Target”, you have to put the real URL of your website so SiteCheck can scan it.

EDIT: I have to clarify, what I stated above is true for most cases, but in your website it seems that the installation path is using a letter that is in caps, so instead of being newsite you are using Newsite, SiteCheck doesn’t understands this and decides to send the request to the first one which doesn’t exists, that is why the plugin doesn’t works in your installation. You will have to use the website for now until we can fix the issue, or you can change the name of the directory to be all in lowercase.

Marking as resolved, feel free to re-open if you need more information.

[1] https://sitecheck.sucuri.net/
[2] https://www.cantabsrowing.org.uk/
[3] https://www.cantabsrowing.org.uk/Newsite/

Thanks for your prompt and helpful reply. It will be difficult to change the folder name as so many links, both internal and external, depend upon it. I hope it’s possible to fix this in a future release as your plug-in seems very effective and highly thought of. I use it with both success and confidence on several other sites I maintain.

This is not a problem with the plugin, so a new release will not fix it. The problem is with the code that powers SiteCheck [1] which is the server that is being used by the plugin to scan your website. Even if the plugin sends the correct URL, the API service will still try to scan the lowercase version of the address.

I already talked with my co-workers, and more specifically to the developers who maintain that code base, they will make the appropriate changes if necessary, some of these business decisions are taken because some of our customers have a special setup so am not sure if this is going to change soon or not.

ALTERNATE SOLUTION: You could create a symlink between then directory with the uppercase character into one where all the letters are in lowercase, this way you don’t have to change anything. You could also create a redirection rule in your access control file, in fact, this sounds like the real solution to me and you can apply it immediately.

[1] https://sitecheck.sucuri.net/

Thank you. The redirection rule seems like a good idea. I would probably not have thought of that – so thanks again.