On 2 pc' s (Windows 10, build 10240 RTM) I installed ESS 9.
When printing a webpage from the Windows Edge browser, print jobs keep pending and won't print.
The same page printing from Internet explorer (installed on the same computer) just works fine.
When I disable the protection from ESS (with the firewall still enabled) print jobs are successful.
So there must be a kind of conflict between the Edge browser and ESS. I tried several advanced settings within ESS, but without any result.
Only with ESS protection disabled print jobs are finished!
I was having the same problem on 2 computers. I reinstalled ESS V8 on one of them again, and the printing problem was gone!