An Error is a mismatch between a monitoring expectation and a monitoring result.
Errors point to actual risks and potential areas of risk that hamper interactions with a monitored target.
Each error is followed by diagnostic information to pinpoint the cause of the error. The type of diagnostic information – DNS trace, HTML page snapshots, Media stream parameters or videos captured during script playback etc – is dependent on the monitoring task type and type of error. If the error is the result of an HTTP status response code, you can look up the HTTP status code here. The most flexible tool for obtaining full details on an error is an Online Report.
If a Device contains more then one Task, then each error detected by any of the tasks in the Device will result in a Device error. Furthermore, a device filter will then determine if an alert is sent.