I got error this "Empty publish transactions result in a warning" error, when i published the page from the parent publication and select the "Also Publish/Unpublish in Child Publications" publishing. any suggestion to resolve this issue.
This means that for some reason the publish instruction resulted in 0 items to publish. Maybe the structure group is set to not be publishable, or some other reason. Pre Web 8 this would have been reported as a success, with 0 items published, which I think is worse :)
Might be worth running your publisher in debug (stop the publisher service then run
tcmpublisher /debug) to find out why it is resulting in a 0 item transaction.