Encrypted emails are not showing up in a shared mailbox on outlook client but are showing up in Outlook web app

I have a shared mailbox to which encrypted emails are sent. These encrypted emails are showing up in outlook web app when this shared mailbox is opened as an additional mailbox. The encrypted emails donot show up in the outlook client when the shared mailbox is auto mapped to the user's profile. But, these mails show up in outlook client when I open shared mailbox as a new profile. Can anyone suggest what should be done to so that the encrypted emails show up in the auto mapped shared mailbox in user's profile.