Extract tnef

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Right click on one or more Tnef file(s) on your desktop and select Convert with Filestar.
Type extract in the search box.
Press Extract.

What is .tnef?

Name: Transport Neutral Encapsulation Format
Extension: .tnef
Category: Email
Developer: Microsoft
Description: File generated by Microsoft Exchange email programs such as Outlook; appears as an email attachment for email clients that don't recognize Microsoft's proprietary TNEF format; may cause the text "application/ms-tnef" to appear in the email if the email client does not recognize Microsoft Exchange formatting.
MIME Type: application/vnd.ms-tnef
Wikipedia: .tnef on Wikipedia