1. A computer monitoring system comprising: a memory storing a computer program, the computer program configured to perform computer system monitoring activities when executed; and a data processing apparatus configured to execute the computer program, wherein when the computer program is executed the computer monitoring system is configured to perform computer monitoring activities; to collect information regarding computer system status during the computer monitoring activities; to detect a problem in dependence on the information collected during the computer monitoring activities; and to determine whether to launch a diagnostic probe when the problem is detected.