… but the ticket is marked as solved… while the problem is not!
So, same problem here: incompatibility between fusion-core and enewsletter
You are aware of this problem since may 2016, and there is no update ?
No one thought about the possibility of creating a newsletter on another WP installation (without core fusion) and then exporting the newsletters and finally importing them into the WP where fusion core is installed ?
I find a bit odd that newsletters can not be exported / imported … unless I have not seen all the options, and I would glad you to showed me how to do it!