If you need to delete some of the unwanted record or log you can do that operation on this setting. Different helpdesk logs can be cleaned from here depending upon the date that is selected for the logs.
Clean logs before: Date and time can be selected and the logs that are present before that particular date selected will be cleaned.
Error log: All error log file will be cleared.
Parser log: Parser log are details about all incoming e-mails which can be emptied by selecting this option.
Sent email log: It will clear all the sent mail logs for the date that is mentioned for it.
Gateway transactions log: It will clear all Gateway transactions log for the date that is mentioned for it.
Activity log: It will clear all Activity log for the date that is mentioned for it.
Audit log: It will clear all Audit log for the date that is mentioned for it.