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Email exceptions reports may include information about encrypted emails which cannot be opened. Two common encrypted emails are Secure/Multipurpose Internet Mail Extensions (S/MIME) emails and restricted permission messages (RPMSG).


S/MIME emails include a digital signature added by the sender to verify his or her identity. The recipient has public key which is used to encrypt the message, and a private key which is used to decrypt the message. So S/MIMEs serve a dual purpose by both authenticating the author, and protecting the contents of the message. Microsoft Exchange supports S/MIME.


RPMSG messages are Outlook encrypted emails which may be set to prevent them from being printed, forwarded or copied by a recipient. A message with restricted permissions will have the extension 'rpmsg', and may appear as an attachment in another email. It will not be possible to open the message unless you are using the account of the recipient, and it may be necessary to use Outlook's specific rights management system. It may still be possible to review these messages by having the original custodian collect his or her email data.





A study by a consulting firm named Creative Strategies shows that younger workers under the age of 30 have shifted away from using email to communicate for business and toward using cloud based office software, particularly that offered in the Google Docs editors suite. While more than a third of those over 30 surveyed made use of Outlook frequently to communicate with business colleagues:


. . . only 13% of workers under 30 listed Outlook as a tool they used to collaborate at work:



The younger generation is shifting away from email focused communications and relying more on video conferencing software and text messaging.

When reviewing .msg files in Windows Explorer, it's common to get a message reading, "Either there is no default mail client or the current mail client cannot fulfill the messaging request. Please run Microsoft Outlook and set it as the default mail client."


If you right click on a file and select Open with . . . you can set the option to always open .msg files with Outlook.



This should stop the error message from coming up in most cases. However, it will still appear when you try to review the files in the preview mode in Explorer if you are running a 32 bit version of Outlook on a 64 bit operating system.


Also try disabling add-ins for Outlook, such as the Adobe Acrobat add-in, if the problem persists.

Sean O'Shea has more than 20 years of experience in the litigation support field with major law firms in New York and San Francisco.   He is an ACEDS Certified eDiscovery Specialist and a Relativity Certified Administrator.

The views expressed in this blog are those of the owner and do not reflect the views or opinions of the owner’s employer.

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