When you send a message with an attachment, Direct Mail may warn you that the attachment is too large. This can be for one of two reasons:
- Many email gateways do not allow messages larger than 10 MB in size.
- e3 Delivery Service limits the maximum message size in order to ensure speedy delivery of your email campaign.
Alternatives to attaching large files
Rather than attaching a large file, it is better to instead email a link where the recipient can download the large file. For example, you could save the large file to Dropbox or another online hosting service and then share the link via email.
If you are sending via e3 Delivery Service and require the ability to attach exceptionally large files, please contact Direct Mail Support.
Why attachments seem to “grow” in size
When you attach a file to your message, you may notice that the attachment size listed in Direct Mail is roughly 33% larger than the file size listed in Finder. For example, if you attach a 1 MB PDF, Direct Mail may show it as being 1.3 MB in size. The reason for the discrepancy is that files must be encoded in a special way before they can be attached to an email message. This encoding process usually increases the size of the attachment by about 33%. In order to help you accurately gauge the size of your outgoing email, Direct Mail shows you this larger, encoded size.