MailManage read an email, execute command which are in it and send result back. If you use gmail account you will check that your account let less secure apps use https://support.google.com/accounts/answer/6010255?hl=en Exmaple email: BEGIN# pwd# echo HELLO WORLD!!!# ifconfig# END# Answer: out: /home/rpark/Mailer HELLO WORLD!!! eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet xxx.xxx.xxx.xxx netmask xxx.xxx.xxx.xxx broadcast xxx.xxx.xxx.xxx inet6 e80::f90:9ca2:da48:1781 prefixlen 64 scopeid 0x20<link> ether 80:52:d7:43:1c:d3 txqueuelen 1000 (Ethernet) RX packets 2762355 bytes 420575091 (401.0 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 449763 bytes 129386970 (123.3 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 device interrupt 20 memory 0xfe300000-fe320000 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 448357 bytes 230113991 (219.4 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 448357 bytes 230113991 (219.4 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet xxx.xxx.xxx.xxx netmask xxx.xxx.xxx.xxx broadcast xxx.xxx.xxx.xxx ether 80:52:d7:43:1c:d3 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 errors: