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Apple System Updates (and some other Installers) seem to set the

permissions of / to 775 or 777.



I have gotten into the habit of



sudo chmod 755 /



after any System Update.



>Now it won't receive incoming mail. Arrrrgh.



Check /System/Library/StartupItems/Sendmail/Sendmail



It should contain the lines



/usr/sbin/sendmail -L sm-mta -bd -q1h &

/usr/sbin/sendmail -L sm-msp-queue -Ac -q 20m &