New Curve on Verizon connected to three (3) POP mailboxes on an independent ISP (Powweb).
The mail comes in to both mostly: sometimes, mail will appear on the Curve but not on the desktop.
I think it's a race condition on which one will mark it "Read" first, but that would mean that it would never appear on both (it mostly appears on both).
What do you use on the desktop (PC?) for email? For instance, inm outlook express there's an option to leave messages on the server. If that option is not set, the messages will delete automatically. So if the message gets to the desktop first it may not make it to your BB.