[oogali]

I dunno what Hotmail is based on, but Microsoft Exchange slows down with the increasing number of items in your inbox, not necessarily message size.

Maybe they're using the same message store?

[rbanffy]

A client that uses Exchange has to limit internal mail-boxes to 100 megs. If you want backups, move messages to a .pst and copy it to a network share...

I think that reliance on Exchange is a huge mistake.

[Locke1689]

No, it's a lot more complicated than that. Actually, what you're suggesting just doesn't scale.