A solution is proposed for managing a plurality of computing machines. A corresponding method comprises causing each computing machine of at least part of the computing machines to execute a management activity on the computing machine; receiving a corresponding result of the execution of the management activity on each computing machine; determining a success fingerprint according to one or more characteristics of each of at least part of one or more wherein the corresponding result is indicative of a success of the execution of the management activity thereon; calculating a similarity index for each of one or more failure ones of the computing machines wherein the corresponding result is indicative of a failure of the execution of the management activity thereon; and prioritizing the computing machines which failed to accept a policy according to the corresponding similarity indexes.