I am also facing the same problem what you mentioned in your question. I am spending my daily time to troubleshoot this.
Although I have tried with new provisioning of master image of Windows 10-1809 and successfully created desktop pool as well as updated desktop pools. But when I updated this master image for windows patching then with that new snapshot on same master not allowing to create new desktop pool as well as not allowing to update existing one. I am using Horizon 7.7. When I push this new snapshot to any pool for updation I get the error message like "Published Failed".
I have prepared 2 to 3 separate master images to cross check but with every master image I can create pool with 1st snapshot without windows update. In case I install any another software and push image with new snapshot, it shows error "Published Failed"
I have some master images from last year too where I can create pool from old snapshot but if I try to create another pool with new snapshot, after pushing it to pool, it will give error "Published Failed"
