Difference between ZAP and Disable Mailbox

ZAP = deletion of hidden messages, folder archiving rules and stuff.

Basically, when you are disbling a user for archiving, it just sets your archiving status = disabled, but leaving all your custom policies in the mailbox itself intact (i.e. custom settings for a folder in Outlook), as well as the "hidden message" with some more general settings in it.

With Zapping, you delete everything out of the mailbox as regards to Enterprise Vault, all settings, all custom settings, all permissions and stuff.

Zapping is most likely used when e.g. an employee leaves the company and you want to archive all his data regardsless of his own custom policies set, or when you are having trouble archiving a mailbox where you suspect that the hidden message might be corrupt, something like this.

Cheers