Below are the instructions to identify the incident and the solution provided:
Symptoms
Users receive spam messages that should have been detected by Panda Cloud Email Protection.
Solution
Several actions can be taken to resolve this issue:
Increase the detection level to 9 for the affected users or domain. To configure this option, go to Filtering mode and increase the level from 5 (default) to 9.
Feed the anti-spam engine. To complete this task, select the wrongly classified messages either from the administration or user web console or from Notifier and click the Spam button.
Add the sender to the blacklist, particularly if the email has been received more than once from the same sender. In order to do so, click the Spam folder, select the message wrongly classified and click Blacklist.