There is another thread on this topic that describes an edit you can make to lib/W3/AdminActions/CdnActionsAdmin.php to fix this:
V 0.9.3 CDN Cloudfront Error - Empty Access Key
It worked for me.
There is another thread on this topic that describes an edit you can make to lib/W3/AdminActions/CdnActionsAdmin.php to fix this:
V 0.9.3 CDN Cloudfront Error - Empty Access Key
It worked for me.