Re: limit on blind copies?

> I have a user who is blind copying 227 users from another email system.

First and foremost, that's abusive practice. Bcc is not intended to be used
this way. The user needs to set up a mailing list instead.

That said, the effect of doing 227 Bcc's is going to be one of two things:
(1) A single copy of the message will be sent with those 227 addresses
in the envelope but not in the header, or (2) 227 or more separate copies
of the message will be sent, each with with a different header.

(2) is the preferred approach because it gives a clear indication to Bcc
recipients of their status, but most clients don't want to bother and so
implement (1). But we can't be sure of that.

Without knowing which of these is going on, it's really impossible to say
what the possible problems are because their characteristics are much too
different.

> If the account has a forward set (which 47 of them do) it forwards on fine.  If
> not, NOTHING HAPPENS and I get a bounce back the next day saying: "Delivery is
> delayed to these recipients or groups".

Delay != bounce. Assuming you are getting a delayed notification from your
own system, that means the message(s) are stuck in a queue somewhere. What
does a history command in imsimta show?

> I checked configutil for some sort of threshold setting.  I can't understand
> why I haven't encountered this before.  Anyone have any ideas?

There's not enough information here to even begin to guess as to what the