Change allowed mail size quota

Question

The email server on my ubuntu machine can only receive mails up to 10 megabytes in size. I would like to change that value, but I'm so blind I can't figure out where to change it.

Could not be delivered because of

Server refused mail at MAIL FROM - 552 5.3.4 Message size exceeds fixed limit

Answer 1

If you use Postfix

• add "message_size_limit = 102400000" in "/etc/postfix/main.cf"
• reload postfix: sudo postfix reload
• check message_size_limit

Example(100Mb):

$ sudo postconf message_size_limit
message_size_limit = 102400000

This is documented on the Postfix site:

message_size_limit (default: 10240000)

The maximal size in bytes of a message, including envelope information.

Note: be careful when making changes. Excessively small values will result in the loss of non-delivery notifications, when a bounce message size exceeds the local or remote MTA's message size limit.

Answer 2

Open /etc/postfix/main.cf find message_size_limit and change it from 10240000 (10mb) to e.g. 20480000

Answer 3

Get:

postconf -n | grep message_size_limit

10240000

Set:

sudo postconf -e 'message_size_limit = 31457280'

Get (to see if it worked):

postconf -n | grep message_size_limit

31457280