Text Box: Many users ask if LISTSERV allows attachments to be sent to JISCmail lists.  The simple answer is yes and is applicable to the vast majority of our lists, as the default for the access control keyword ‘Attachments =’ is yes.
Many owners prefer not to allow attachments because if large, can block up users mail boxes and can also carry viruses.  For this reason some of our list owners configure their list(s) to reject attachments and use the file area instead (Please see later article).  Listed below are the various ways in which you can use the Attachments keyword
Attachments= Yes	
All types of attachments are allowed to be posted to the list (the default).  Note however that other configuration options may still disallow the posting of certain attachments, and that "Attachments= Yes" does not override them.  For instance, if you have "Language= NoHTML", setting "Attachments= Yes" does not override the Language= setting.  Or if you have "Sizelim=" set to a value that precludes a file of x number of lines from being posted to the list, setting "Attachments= Yes" will not override the Sizelim= setting if the message with its attachment exceeds the number of lines specified by Sizelim=.
Attachments= No	
All types of attachments are disallowed, other than plain text (always allowed) and HTML text (which is controlled exclusively by the "Language= NoHTML" keyword setting). With "Attachments= No", LISTSERV rejects messages containing attachments and bounces them back to the poster.
N.B. The reason HTML text is not subject to "Attachments=" filtering is to allow you to reject (bounce) messages with attachments, while silently suppressing HTML text in multi-part messages which also contain a plain-text alternative.  Some mail programs send both HTML and plain-text versions of messages, and, even if you do not want HTML text on your list, there is little point in keeping out people who use it (who are often new to the Internet and aren't aware that their mail programs are sending HTML text) when you can simply remove the HTML part. 
Attachments= No,Filter	
Same as "Attachments= No", except that LISTSERV simply removes the unwanted material from the message and processes it instead of rejecting it out of hand. The removal of material is a silent operation and the poster is not notified that the attachment was discarded.
N.B. In all three of the above cases, when a message containing one or more uuencoded files is posted to the list, the encoded file(s) is/are stripped from the body of the message and the remainder of the message is passed through to the list. 
Attachments= All
This setting tells LISTSERV to allow inline, uuencoded files, such as are generated by Microsoft Outlook, overriding the default.
N.B. One important restriction: UUencode filtering is strictly on/off. There is no attempt on the part of LISTSERV to guess file types when filtering is enabled (the default). 
Text Box: Tips for Owners - Attachments by Pam Delaney


JISCmail 2004

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