My open rate statistics are not available. What may be causing this?
If your open rate is zero, no worries! It does not necessarily mean that your messages haven’t been opened.
Plain-text messages, due to their intentionally simplistic format (no images), cannot be tracked in your open rate statistics, unlike HTML designed messages. So, if you send a plain text message or a subscriber chooses to open your HTML message using the plain text option or does not load images in his email, it is not counted as an open.
Also important to remember is that any message you send as plain-text will always show an open rate of zero, no matter how many subscribers open the message.