PidTagAttachExtension Canonical Property
Applies to: Outlook 2013 | Outlook 2016
Contains a file name extension that indicates the document type of an attachment.
||PR_ATTACH_EXTENSION, PR_ATTACH_EXTENSION_A, PR_ATTACH_EXTENSION_W
These properties are set by the client application at submission time.
The messaging system uses PR_ATTACH_EXTENSION when converting message attachments (in-route conversion) or launching applications based on attachments in received messages. If the sending client does not provide a value for these properties, the message store handling the attachment is not obligated to generate it. The receiving client should first check for PR_ATTACH_EXTENSION, and if it is not provided, should parse the file name extension from the attachment's PR_ATTACH_FILENAME (PidTagAttachFilename) or PR_ATTACH_LONG_FILENAME (PidTagAttachLongFilename) property.
Handles message and attachment objects.
Provides data type definitions.
Contains definitions of properties listed as alternate names.