When you add a YouTube or Vimeo slide to a slideshow, MetaSlider automatically downloads a thumbnail for the video directly from the YouTube or Vimeo servers.
In some cases, this process fails and your slideshow will display a broken image in place of the Video thumbnail. The video will still play, but the thumbnail will not display.
This can happen for 2 reasons:
1. The video has been set to private on vimeo.com
This stops MetaSlider from being able to retrieve a thumbnail for the video from the Vimeo servers.
2. Server Firewall
Your server may be set up to block requests to the Vimeo and Youtube servers as a security measure.
You will need to contact your host and ask them to unblock the following URLs from the server firewall:
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