Why do I see SIZE errors in the SMTP log?
In the SMTP log, I have found the following two lines (split onto several lines here):
SMTP 13 Mar 2 00:19:28 F 3209 89207 SIZE error 3800 3771 email@example.com firstname.lastname@example.org SMTP 13 Mar 2 00:19:29 S 3016 89207 local mail 00192902538455 email@example.com [22.214.171.124] firstname.lastname@example.org 4040 bytes
It says that there is a "SIZE error". What does this mean? Should I be concerned?
When external mail servers send messages, they have the option of saying how large the message is (the Enhanced SMTP SIZE option). This allows GMS or GMS Webmail to reserve the correct amount of disk space to allow the complete message to arrive and be delivered. In this example, the remote server indicates that it wants to send a message with 3771 bytes. GMS or GMS Webmail will then reserver 3771 bytes of disk space to hold the message as it arrives.
Normally, the message arrives, is delivered and no "error" message is written into the log.
However, some remote mail servers give the wrong size of message. In this case, the message really was 3800 bytes long, not 3771 bytes. GMS or GMS Webmail notes this fact in the log but processes the message as normal. The message is correctly delivered as can be seen in the second line in this log extract.
As a user or administrator, there is no action to take since no messages are lost or returned to sender. You may wish to contact the administrator of the sending server to tell them that is incorrectly calculating SIZE information since this may affect other, less tollerant, messaging systems.
Keywords:SMTP, Size, error, delivery