Errors listed here are not the direct result of a broken link on your site. Instead they come from:
- someone requesting a non-existing page on your site (usually a robots)
- Joomla or an extension having a bug and triggering a fatal error
The fatal errors are particulary an issue because it means one of your visitors was faced with a full-on error while trying to do something on your site. This is a very bad experience, especially if they were trying to register, post a message or worse, buy something from you.
Non-existing pages requests
This would usually not require any action but you still need to browse quickly through them in case they are for images or other resources that may be missing.
These errors must be tracked down and fixed. 4SEO is usually capable of recording details about the error such as the file name and the line number the error originated at.
This should at least provide enough information to identify the faulty extension or code area where to look at.
Make sure to fix PHP fatal error reported by 4SEO
These errors are very bad for your visitors and search engines. For both, they will be the sign of a low quality website.
You risk losing traffic, content and sales in all cases.