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SMTP component for delphi that is absolutely free.

aerokevs asked
Medium Priority
Last Modified: 2010-05-18

I was wondering where can we get a SMTP component that is absolutely free. I used the Built in SMPT component in Delphi 6 but it returned an error. saying "invalid command sequence".
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in delphi 6 you probably used Indy components, right?
well, generally, i had very good experience with these components. i believe there is a solution to your problem, though you need to supply more details..

generally speaking, i would recommand to download the latest version of Indy (version 10). it's an open-source project.


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Mohammed NasmanSoftware Developer
TheRealLokiSenior Developer

personal preference would be the Indy components for SMTP,
although for almost anything else, I'd use Francois Piette's ICS (internet component suite)


using the indy component i encountered and error saying "invalid command sequence" and "we do not relay <email address>';
TheRealLokiSenior Developer
you'd likely get those problems no matter what component you used then
"invalid command sequence" means just what it says, you have sent a command in the wrong order, or the server was expecting a command before the data you sent.

the "we do not relay" is a common occurrence with ISP's these days. In an attempt to reduce the number of spammers using them as launching pads, they either only allow smtp from trusted sites (other mail servers), or require an authorization first.
try smtp to your local isp's mail server and you wont have this problem.



what do you mean by try smtp to your local isp's mail server?

TheRealLokiSenior Developer

Let's say you connect to the internet with "SpeedyNet.com" and they have their mail server as
"smtp.SpeedyNet.com" port 25
Your friend connects to the internet with "MegaNet.com" and they have their mail server as
"smtp.megaNet.com" port 25

If you want to send an email from "MyMachine" to "MyFriend's email address"
the *nomal* travel would look like this
[Mymachine] smtp mail to smtp.Speedynet.com port 25
[smtp.Speedynet.com] Recives mail, sees it is for ...@MegaNet.com, and queues for delivery
[smtp.Speedynet.com] sends mail to MegaNet.com port 25
[MegaNet.com] Recives mail, sees it is for itself (...@MegaNet.com), and puts it in "myfriends" email mailbox.
[MyFriend] connects to pop3.MegaNet.com port 110 and downloads his mail
[MyFriend] sees it is an offer for a free diploma, and marks it as junk mail...

If you were to try to send to smtp.SomeOtherServer.com port 25, and have *that* server send the mail to MegaNet.com, you would likely get the "we do not relay" error
This is because the smtp mail servers are checking your ip address against their list.
They typically allow any ip address that is issued by themselves (ISP), and other known mail servers, but deny others.

so... if you set
IdSMTP1.Host := 'smtp.MyISP.com'; // eg. 'smtp.Speedynet.com';
then your ISP's mail server is unlikely to reject it.


so what should i do in order that my mail will go smooth? Acutally i am using an ip address instead of the name.


guess i have to request for a refund.. no further answers were added.
TheRealLokiSenior Developer

well... the correct answer to your question "where can we get a SMTP component that is absolutely free."
was answered by ewilde and mnasman in the first 2 answers.
That error has something to do with the server you are connecting to, and how you are connecting to it, so that is your real problem.
Forced accept.

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