Double ehlo appears to be preventing Mailsend.exe from working

[MatthewALHardy]

Hi,

I have a client using Office 365 hosted exchange. When testing manually from putty I note that each time I connect, the first time I issue either a helo or ehlo command. I received "500 5.3.3 Unrecognized command '????'" but then if I issue exactly the same command again I receive the expected response. I believe that this is an anti spam measure. When I test from mailsend1.20b.exe the command fails. Does anyone know if it's possible to tell mailsend to retry the ehlo command if it fails the first time?

Command and response as below

mailsend1.20b.exe -to [email protected] -from [email protected] -domain clientdomain.com -smtp clientdomain-com.mail.protection.outlook.com -sub "Subject LIne" +cc +bc -v < d:\path\file.LOG Connecting to clientdomain-com.mail.protection.outlook.com:25 Will detect IPv4 or IPv6 automatically

libmsock: using getaddrinfo AF_INET IPv4 IP address: xx.xx.xx.xx:xx EINPROGRESS=10036,EWOULDBLOCK=10035 connect(): socket=332,rc=-1, errno=10035 Try socket 332 Setting read timeout to: 5 seconds Windows Setting read timeout to: 5 seconds [S] 220 CY1NAM02FT061.mail.protection.outlook.com Microsoft ESMTP MAIL Service r eady at Fri, 11 Oct 2019 16:40:13 +0000 [C] EHLO clientdomain.com Setting read timeout to: 5 seconds Windows Setting read timeout to: 5 seconds Winsock error[10060]: A connection attempt failed because the connected party di d not properly respond after a period of time, or established connection failed because connected host has failed to respond.

Error: Connection is closed unexpectedly Error: EHLO failed [C] MAIL FROM: [email protected]

Setting read timeout to: 5 seconds Windows Setting read timeout to: 5 seconds Winsock error[10060]: A connection attempt failed because the connected party di d not properly respond after a period of time, or established connection failed because connected host has failed to respond.

Error: Connection is closed unexpectedly Error: MAIL FROM failed: '-1 ' Could not send mail