This error means CoSchedule couldn't send an image in your message to Facebook. It can happen on any plan.
What the error says
Facebook encountered an error because your message contains a missing or invalid image.
Why it happens
Usually the image is too large or in a file type Facebook doesn't accept, or the upload to Facebook failed.
Fix it
- Open the message on your calendar.
- Check the image against the Facebook limits in Image, video and GIF sizes for social messages.
- Remove the image from the message.
- Upload the image again from your computer, resized or converted if needed.
- Reschedule the message.
If it still fails, contact support.
Prevent it
Resize and compress large images before you upload them, and use a file type Facebook accepts.
Facebook noticed some irregularities with the image associated with this message
CoSchedule no longer shows this warning. It appeared on link messages when the link's preview image wasn't ready yet, and it didn't stop the message from publishing. If a link message shows the wrong image, see Fix a wrong link image or missing link in a social message.