IMPORTANT:  LISTSERV 16.x web interface customizations and branding 
are NOT COMPATIBLE with LISTSERV 17.5!

Before upgrading to LISTSERV 17.5, please be sure to back up your LISTSERV installation.

PLEASE read the LISTSERV 17.0 What's New document before upgrading!

(Yes, this is not a typo; we mean the LISTSERV 17.0 What's New document.)

It contains a great deal of information about the new version of the interface.


LISTSERV 17.0 was a major upgrade to the traditional LISTSERV web interface, bringing it in line with present day standards with responsive templates designed to display on both desktops and hand-held devices.  While there is a backward-compatible interface mode that allows both the server interface and individual list interfaces to fall back to the non-responsive 16.x “look and feel,” customizations made to the 16.x web templates are not compatible with the 17.0 web interface and will have to be retooled to fit into the new responsive interface.  If your LISTSERV server has heavily-customized or branded templates, L-Soft strongly recommends that this retooling be done in a test environment before upgrading your production server.


Before installing any upgraded files, the LISTSERV installer scripts for both Windows and unix will copy SITE.WWWTPL (if it exists) to SITE165.WWWTPL.  This is a requirement for the “compatibility mode” previously mentioned, and preserves any customizations made to the 16.x web templates for use by that mode.


LISTSERV sites that normally upgrade using manual methods rather than using the installer kits MUST perform the SITE.WWWTPL -> SITE165.WWWTPL operation manually.  Unix LISTSERV sites performing this manual operation MUST ensure that the resulting site165.wwwtpl file is named in lower case, is owned by ‘listserv’, and has the same permission settings as site.wwwtpl.