LM5 can't send an email

[Fahd]

Hi, 

I'm using this script in all of our projects to send a backup each month.
One of the LM5 can't send it anymore and  got this in the logs

* string: connection refused 
* nil
* string: Send Mail

NB: LM5 is connected to the ethernet.

What could be the issue?

Code:

--***************************************************************-- --*** For FW spaceLYnk 1.2.1 and FW homeLYnk 1.5.1 or higher ****-- --***************************************************************-- --** Email backup as attachment created by Erwin van der Zwart **-- --***************************************************************-- --********************* Start of parameters *********************-- --***************************************************************-- --Gmail (smtp) username !IMPORTANT! user = 'xxxx' --Gmail (smtp) password !IMPORTANT! password = 'xxxx' --Sender for e-mail from = '<xxxx>' alias_from = 'From me' --Recipient for e-mail to = '<xxxx>' alias_to = 'To you' --Subject for e-mail subjectpart1 = 'Back-up file' subjectpart2 = 'xxx' --Message on bottom of email (will only be showed when client don't understand attachment) epilogue = 'End of message' --***********************************************************-- --******************** End of parameters ********************-- --***********************************************************-- --********** DON'T CHANGE ANYTHING UNDER THIS LINE **********-- --***********************************************************-- --Create table to include mail settings local settings = {     from = from,     rcpt = to,     user = user,     password = password,     server = 'smtp.office365.com',     port = 587,     secure = 'tlsv1_2',         starttls = true, } --Create attachment src = 'backup-' .. os.date('%Y.%m.%d') .. '.tar.gz' dst = '/home/ftp/' .. src -- prepare files for backup os.execute('sh /lib/genohm-scada/web/general/backup.sh') -- create cleanup archive os.execute('cd /lib/genohm-scada/storage && tar -c -z -f ' .. dst .. ' ./') --Create subject subject = subjectpart1 .. ": " .. src .. " " .. subjectpart2 --Load required modules to send email with attachment local smtp = require("socket.smtp") local mime = require("mime") local ltn12 = require("ltn12") --Create e-mail header settings.source = smtp.message{ headers = {           from = '' .. alias_from .. ' ' .. from .. '',           to = '' .. alias_to .. ' ' .. to .. '',           subject = subject }, --Load attachment inside body     body = { preamble = "", [1] = {        headers = {          ["content-type"] = 'application/x-7z-compressed',          ["content-disposition"] = 'attachment; filename="'..src..'"',          ["content-description"] = '.. src ..',          ["content-transfer-encoding"] = "BASE64",       },                      body = ltn12.source.chain(       ltn12.source.file(io.open(dst, "rb")),       ltn12.filter.chain(       mime.encode("base64"),       mime.wrap()         )       )     },       epilogue = epilogue   } } --Send the email r, e = smtp.send(settings) --Create alert when sending gives an error with error message if (e) then   log (e)   log (r)   alert("Could not send email: ", e, "\n") end log("Send Mail") --Delete created backup file from tmp folder inside HL os.execute('cd /lib/genohm-scada/storage && rm -rf user userlib.luas blockly.luas initscript.lua helpers.js genohm-scada.config filter*')