[quote user="jbrowne"]

thanks Thomas.

appreciate your quick response.

does this mean that even a Pegasus xtension could not do it?

[/quote]

I would suspect that the only way an extension could do this is to create a tool to add the attachments and I'm not all sure that would be possible.  Most of the file operations are done with windows calls but the actual attachment is not added until you hit the send button.  You could create a User Defined Gateway to do this sort of process and then build you own program to text the total size of the PMX file that was created.  Really all you could do there though is to delete the PMX file and popup some sort of warning.  Way, way more trouble than it's worth.

Is it possible to have Pegasus mail prevent even attaching a file of size greater than "x" ?

Displaying a message to the user.

Currently, we use our mercury mail server to bounce the message back if it is too large, but when a user tries to attach a big file, then Pegasus seems to freeze up. 

Nope.  I am assuming that the senders are sending via MercuryS rather than the spool queue though.  If you were sending via the queue you might be able to limit the users quote for the spool directory to prevent then from writing a message to the queue greater than a specific size.   Could cause other problems if they want to send two smaller messages that exceeded the size though. 

thanks Thomas.

appreciate your quick response.

does this mean that even a Pegasus xtension could not do it?