Open RPMSG File

Open MSG File

MSG or Outlook Item file format is used by Microsoft Outlook to store information about various items like e-mails, contacts, tasks, appointments in a file.

MSG file is built upon Compound File Binary File (CFBF) Format which allows storing complex structured information in a binary format in a single file. CFBF allows storing property-value pairs in plain and nested structures.

To open MSG files you can use Microsoft Outlook or other applications which support MSG file format. For Windows you can use:

• MSG Viewer
• MsgViewer Pro
• Email Open View Pro

For Mac OS:

• SeaMonkey
• MailRaider
• Klammer

If you open MSG file in Microsoft Outlook you can convert it into multiple other file formats including TXT, RTF, HTML, MHT. If MSG file contained a task you can export it to ICS or VCS file format.

If you want to open MSG file to see its inside structure, there is a tool available from Microsoft which was developed to open and display files in CFBF format (as noted above MSG file format is based on CFBF). This tool is called OffVis and it can open any CFBF file, parse its internal structures, and show its contents in a tree like structure with data types, size and offset displayed. When user clicks on any data element OffVis tool will navigate to a raw binary offset where that element binary data starts. OffVis 1.0 Beta could be downloaded from Microsoft Technet OffVis page. More useful information about MSG format structure and how to interpret its binary form could be found in MSG File Format post on Microsoft Developer. Please note, that interpreting binary data requires computer engineering knowledge experience.

RPMSG file format is quite similar to MSG with major difference that content of e-mail is encrypted, and DRM information added to it. DRM information specifies who can open that e-mail and what forwarding and other rights are available for it. Client application will need to contact DRM server and receive a DRM license in order to decrypt and operate on a message. For more information about DRM server and license check [MS-RMPR]: Rights Management Services (RMS): Client-to-Server Protocol.