But subject is not empty.
How can I fix this problem?
I tryed different ways of fixing it, but nothing has helped me.
SMTP was on and off, subject with tags or without — there was no difference.
Diagnostic tests were successful — I got two e-mails.
I installed clean wordpress (3.9.2) and got the same error.
Later I’ve fixed the subject error, but I got ERROR – 14.2 MB – mail> Message body empty.
Maybe the plugin is not compatible with new versions of wordpress?
But I can’t find the same problem report from other users.