Outlook automation with encrypted signed email

Hi,

I recieve a digital signed email daily which contains a zip file. I would like to know if there is a way to automate the extraction of this attachment.

I have tried all standard methods but where I run into problems is with the fact the email is encrypted when recieved. It required someone to manually open the message, as it won't appear in the preview pane, before the macro can access it. It always returns nothing and fails with the following statement ...

Set thisMail = myFolder.Items.GetFirst()

Is there a way to automatically unlock this message in the macro or is there some other way I should be doing this

Thanks in advance for any insight you can provide.

Christopher New