If your contacts receive blank emails, you may be using only one large image in your email campaign – without text. You want to have a good balance of text and images in your emails so that they are not filtered into the spam folder. If you are sending an image-only email, make sure you have entered some text in the text-version of the mail. Your contacts may also be seeing a blank email because they have not enabled images in their email client.
To avoid this problem in the future, send emails with a fairly equal text to image ratio.
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