Exchange Server - Trigger to purge message in Dumpster

Hi all,

Is there anyone can explain me how the Exchange Server check the messages in Dumpster and purge them please? And how can we force it works immediately.

I'm facing an issue that email items still be retained in Dumpster although the time I configured to keep them just 01 day or just few minutes.

For example:

User setting:

RetainDeletedItemsUntilBackup : False

RetainDeletedItemsFor: 00:00:05

Thanks a lot.