Error reading SMTP packet; response to RCPT TO command expected

Question

Error reading SMTP packet; response to RCPT TO command expected

Hello,
Has anyone come across this error message,

Error reading SMTP packet; response to RCPT TO command expected

They can write to me and I can send them email from a different account (gmail) but not from my main account. They're using microsoft exchange.

Thank you,

G5 PowerMac 2 GHz, MacBook 2GHz Intel Core 2 Duo, Mac OS X (10.4.11), iPods, airports, problems etc.

Posted on Sep 25, 2008 1:53 AM

Reply

Answer 1

BDAqua

Level 10

239,177 points

Sep 25, 2008 3:13 AM in response to Hilary Bowers

Hi Hilary,

How is the address formed? are there multiple names in the TO line?

Are you using CC or BCC?

Reply

Answer 2

Sep 25, 2008 5:04 AM in response to BDAqua

sorry, what do you mean by "address formed" username@server.com is the format. It fails whether there is one or more addressees, CC or TO. Haven't used BCC.

The administrator says this:

"Looking at the error messages that I am getting it could be the problem
we had with the spam emails. It looks like mac email uses a different
port to send its mail. After the work we did on our proxy server and
fire wall to protect ourselves from spam we may be blocking ports that
mac mail use. Mac mail use a different port compared to everybody else
it seems."

This seems odd to me.
Tks.

Reply

Answer 3

Sep 25, 2008 5:08 AM in response to BDAqua

I just noticed I forgot to specify: I am using Mail, .mac account, outgoing mail server is smtp.mac.com

Reply

Answer 4

Sep 25, 2008 6:20 AM in response to Hilary Bowers

Well, before you can send a RCPT command, you probably need to authenticate. 1) check your authentication credentials (user name and password probably) and 2) confirm that you are using the port your smtp server is listening on.

It does not matter that your friend is using an exchange server; it seems it is not getting to your smtp server.

-fred

Reply

Answer 5

Sep 25, 2008 6:51 AM in response to Frederick Avolio

Fred, thanks but surely if there were a problem with either 1) or 2) I would not be able to send mail at all using my .mac account. I can to anyone except to those people, and they receive from everyone (it seems) except for me. I don't know if there are other people using .mac having trouble with them (it's our school)

Hilary

Reply

Answer 6

Sep 25, 2008 7:01 AM in response to Hilary Bowers

Sorry Hilary. Right you are. I misunderstood. It does seem like the sysadmin there needs to fix things. Sounds like the .mac server gets your email and tries to then send to the recipient, and a connection is permitted, but it doesn't like the FROM: (your address).

-fred

Reply