What are all the /var/spool/smtpd/offline/1689525601.XXXXlJ85yQ

Hi all,

I just filled up my whole /var with zillions of files /var/spool/smtpd/offline , dating back to 2018. What are these files and is it safe for me to delete the ones more than a week old?

Thanks,

SteveT

Steve Litt http://444domains.com