As I said, I am not familiar with that plug-in.
It could be that somewhere the path to the plug-in is being specified (home/virtual/site11/fst/var/www/html/cgibin/calendar/calendarscript/plugins/EmailNotify2/templates/default/) and somewhere else "/digest" is being tacked onto it? Maybe try searching the plug-in files for "digest"?
In such a case one or the other may need to be specified without one "/".
I have no idea if that's the cause of your problem though.
Dan O.
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