There is no limit to the number of subscribers (subject only to Nabble's servers capacity).
You should be aware that every subscriber has to confirm their wish to receive emails. You cannot simply add people whose addresses you discover, so you'd need an amazing popular forum to achieve tens of thousands of subscribers, let alone, millions. Further, each subscriber opts whether to receive the first post in a topic are all messages in a topic and whether to receive posts as they are made or as a daily digest.
As a message is posted to a forum it is also placed in a "subscriber queue". In my experience these initial queues are processed within moments of being posted and the message either despatched immediately, added to the digest queue for posting at the next 24 hour slot, or if it is a message not requested by the subscribed, dropped out of the queuing system.
Reliability of mail generation at Nabble is pretty well rock solid. Reliability of delivery is a different issue. Mail servers are known to treat large volumes of similar mail as spam and recipient's own spam filtering may prevent delivery.
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.
Locked
