CUE does not automatically delete messages from the voicemailbox. Only the owner of a personal mailbox can delete messages in the mailbox and members of a GDM can delete messages in the mailbox.
However you can configure IMAP which gives you the ability to read, mark as read or unread and delete voicemails.
The voice-mail messages are downloaded as attachments to e-mail messages. Subscribers can access the voice-mail messages over the network or can download them selectively. If the messages are downloaded, subscribers can play them locally using standard media players without requiring a connection to Cisco Unity Express.
So if you access your mailbox via IMAP you can delete the VMs you want to. Please refer to the following link for more information:
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