Crawl errors are issues reported by search engines as they crawl your website.
Why do Crawl Errors matter?
Almost everything the search engine knows about your website, it learns via a program called a 'spider' which it uses to scan or 'crawl' your website. As this is a fundamental mechanism for search engines to interact with your site, we consider them important enough to check regularly. There are a number of different types of crawl errors and some are reasonably benign, while others are more serious issues. Find out more about crawl errors here.
How are they fixed?
Sometimes things are flagged by search engines that aren’t really errors at all – such as pages that have actually been retired, whose content will never be reinstated. In cases like this, they can simply be left alone and Google will stop reporting them after a while. In other cases, your developer is required to implement “redirects” to resolve the crawl errors. Find out more about redirects here.
Some crawl errors indicate a server configuration issue and should be dealt with by your web developer.