Query regarding attachments received while triggering a process via. email

Hi

I am working on version 19.4. 

My process gets triggered via. an email. If I have .txt or any image file or .pptx file or .xls file as attachment(s); then they get captured in 'msg!properties'.'Attachments'. However if I have an email as an attachment, it doesn't get captured in 'msg!properties'.'Attachments' neither it gets saved in the specified folder nor the process breaks.

My requirement is to capture any of the attachments which are sent with the triggering mail.

Can anyone suggest how to achieve this?

Thanx in advance!!