Sending Email to Distribution or Mailing Lists
There are a number of different types of Distribution or Mailing List. There are simple ones which distribute incoming email to a defined list of recipients. More complex ones may be managed by a list owner who can regulate postings, allowing or disallowing emails from being distributed.
Mailing lists have a size limit to prevent inadvertent or malicious misuse. Sometimes the size limit is published in the mailing list information which you can get from the list server but often you only find out when an email fails to be distributed. Most of the lists hosted at Cardiff University have a size limit of 150 KiloBytes. When an over-sized email is refused by a list it is 'bounced' to the list owner who should inform you of the failure.
You can avoid difficulties by sending documents as plain text or .rtf format files instead of .doc files. For example, a file containing "The cat sat on the mat" is 24 Bytes as plain text, 2000 Bytes as a .rtf file but 20000 Bytes as a .doc file. If you intend sending image files, save them at a low resolution to reduce the size of the email. When calculating the size of an attachment you should add 25% to the file size to allow for encoding.