When a visitor clicks a link but sees that the page does not exist, this situation is usually caused by several types of reasons. When troubleshooting, first determine the scope of impact, then investigate layer by layer; this is much more efficient than guessing one by one.
First determine the scope
Whether a single page cannot be opened or the entire site is inaccessible points to completely different causes. An abnormal single page is most likely a link or page status issue; an abnormal entire site is usually related to server configuration or domain name resolution.
Troubleshoot layer by layer
Is the link address correct? Check the complete address in the address bar and confirm whether the domain spelling, path levels, and file name match expectations. Some servers are case-sensitive, and case inconsistencies can also cause the page not to be found.
Is the page in an accessible state? In the website backend, confirm that the target page has been published, rather than still being in draft or unsynced status. Failing to republish after changes is a common cause of broken internal links.
Does the corresponding file exist on the server? Confirm that the page file indeed exists in the site directory, and check whether file permissions allow access. If a file is moved, deleted, or its permissions are changed, it can trigger the same type of error.
Is domain name resolution normal? Confirm that the resolution record points to the correct server, and whether the binding of the subdomain has taken effect. You can try accessing directly via the server address to distinguish whether it is a resolution issue or a site issue.
Handling and prevention
If the page has indeed been deleted or renamed, the correct approach is to set up a redirect, pointing the old address to the new address, rather than letting visitors see an error page. For addresses that truly do not exist, you can configure a custom error page with clear explanations, providing site search and main entry points so visitors have a chance to continue browsing.
In addition, regularly checking server error logs can help you understand which nonexistent addresses visitors are actually accessing, and thereby discover the sources of broken links—these links may come from in-site navigation or from external references. Once problems are found, fixing them promptly is easier than remedying them afterward.