These articles provide email help for attachments and images.
Inserting images and attaching files to emails sent through your Jackrabbit database is made easy with Jackrabbit files.
It's easy to upload image files and other attachments in Jackrabbit.
Once Jackrabbit files are uploaded you can attach the files or insert the images into your emails.
Procedure to follow to link to Dropbox files in your Jackrabbit emails.