So I was successfully using a origin push method with Amazon CloudFront (using a S3 bucket) but was told that it was preferable to use an origin pull.
1) I deleted the distribution I used for the "push" method
2) I created a new distribution. I kept the same CNAME but went to my host provider and corrected the value so it now reflects the name of the new distribution (which one can get of course on the CloudFront panel)
I have checked that the CNAME is now correctly pointing to the name of the new distribution by using http://www.mxtoolbox.com/
3) In WordPress, through the dashboard, in the W3 Total Cache tab for the CDN, I left the access key ID and secret key fields as they were (i.e. populated with the correct information) even though they are not used (I believe) in an origin pull configuration.
4) In the “Replace site's hostname with:” I entered the name of the new distribution and, under it, i the CNAME field, I entered the CNAME that is now correctly pointing to the name of the new distribution I just created.
However, when I try to test this configuration (using W3 Total Cache test, just below those fields) I keep getting the same error: “Unable to resolve hostname:” followed by the CNAME I’m using.
Surely, I must be doing something wrong. Any tips to troubleshoot this issue?