throw err;
    ^

Error: Cannot find module '/home/pi/SMTP.js'
    at Function.Module._resolveFilename (module.js:470:15)
    at Function.Module._load (module.js:418:25)
    at Module.runMain (module.js:605:10)
    at run (bootstrap_node.js:422:7)
    at startup (bootstrap_node.js:143:9)
    at bootstrap_node.js:537:3