.RPMSG File Extension
File TypeOutlook Restricted Permission Message
What is an RPMSG file?
Email message file created by Outlook, an email and calendar application; stores the message body and attachments, but limits who can view, print, copy, or forward the email based on permissions set by the sender; incorporates encryption so that only authorized entities have rights.
RPMSG files are sent as an email attachment to a standard email message. They use the filename message.rpgmsg.