mutt attachment error

[Haines Brown]

I tried to use mutt to send someone a zip file of about 50 Mb and got
the error: "Error sending message, child exited 1 (). Could not send
message."

I assumed the attachment was too large and so went to
/etc/exim4/conf.d/main/02*/ and altered the configuration to be:

  # Message size limit. The default (used when MESSAGE_SIZE_LIMIT
  # is unset) is 50 MB
  .ifdef MESSAGE_SIZE_LIMIT
  # message_size_limit = MESSAGE_SIZE_LIMIT # I commented this line
  message_size_limit = 200 MB               # I added this line
  .endif

I restarted exim, but it had no effect. 

Haines