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Hi Arjen, 408 errors are timeout type errors so the first thing that comes to mind is what kind of web server you are on. If it is shared then there might have been a surge in traffic to your site or another site on the same host and this slowed down requests enough that the moz crawler got these results returned. You could try running a scan with screaming frog which will scan the site in a similar way to the moz crawler (ie multiple requests at the same time) and if you see the errors there also then this can confirm that the issue is likely with your server setup and not a moz bug.