We have been getting error reports that look like this:


Error occurred while processing file 1793742 from MAILER@LISTSERV.EXAMPLE.COM:


  File is too large to be processed (579119 records).


What does this mean and how do we fix it?


LISTSERV won’t process messages more than 500,000 lines (or "records") long. ‘Number of lines’ is an unusual way to measure message size (it comes from LISTSERV's origins on the IBM z/VM operating system), and doesn’t have an exact equivalent in other measuring schemes, since lines may contain different numbers of characters. The rule of thumb is that 500K lines is roughly equivalent to 30-40 megabytes. So, messages larger than that size won’t be processed; and, since determining who sent a message requires to process it, it means that truly huge messages like this will not get a response from LISTSERV.


The 500,000 line limit is derived from LISTSERV’s site configuration-level FILEMAXL setting. There’s more information about it in this tech tip:


https://www.lsoft.com/news/techtipLSV-issue1-2021.asp