Mail unexpectedly quits - MacBook Pro - macOS High Sierra My Mid 2012 MacBook Pro runs High Sierra 10.13.6 and Mail application version 11.5 modified 01 Oct 2020 by Apple Store Security update 2020-006. Mail worked until today when it quit unexpectedly while using signalspamv2plug-in.
I am unable to re-open Mail despite doing it in Safe Mode.
01 December 2020, sorry to have bothered you all, problem solved by uninstalling the SPAM filter which created havoc.
01 December 2020 - Problem solved by uninstalling the offending SPAM filter, sorry to have bothered you all.