Why can't I send large attachments or pictures?

MailMerge365 only allows you to send Emails with a total size (including all attachments) of 3MB. If you try sending an email with a larger size you will receive an error message response when trying to send that campaign. See here: How do I determine the size of my email with all images and attachments?

If you need to send more, larger or personalized attachments please have a look at our sister product SecureMailMerge which lets you send any size of attachments in a mail merge.

If you didn't attach any attachments it is most likely that the images you used were too big. Even if you resize the images in the email to make them small, they retain their original file size which causes this error message. See here: How do I reduce the size of images in my campaign email?

Why does this limit exist?

  • The way MailMerge365 works is a copy of your original campaign mail is made for each recipient. Therefore if you add attachments to the original email, these will be copied for every recipient and your mailbox size will grow quickly. 
  • Campaigns with attachments will send at a slower speed than campaigns without attachments, because Microsoft imposes limits on how the number of bytes (file size) can be sent per minute.
  • Also it's generally not good email etiquette to send large attachments to recipients because it also causes their mailboxes to grow.
  • Last but not least, by adding the attachment, you lose the ability to track if someone opened that attachment.
  • Note: If you need to send larger attachments, maybe have a look at our sister product called www.securemailmerge.com.

Options for images

See here: How do I reduce the size of images in my campaign email?

Options for attachments

For attachments (e.g. PDFs) or images simply host them on your web server/homepage or a file sharing service (e.g. WeTransfer or Jumpshare). Then add the links to your email like this for example:

Dear Alex, Last time we spoke you showed interest in ACME and I promised to send you our brochure. Have a look at what we can offer.

This way the email is small, can be read on mobile with no problems and when the recipient clicks on the link you'll see this in your campaign reporting.

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