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I can't send email, why?

Possible reason why:

Your Internet Service provider, aka, your dial up, cable, or Internet access provider, have likely made changes to their network in order to prevent sending of email by anything other than the provider's "Outgoing SMTP" setting. This is actually a good policy (for them) since it helps reduce the volume of unsolicited email we all receive.

Example errors when sending:
"503 Valid RCPT command must precede DATA" essentially means that the server was unable to accept the message, usually because the SMTP connection was not properly authenticated.

The downside is that clients attempting to send legitimate email using their web site's domain name (such as, mail.my_domain.xxx) are left scratching their heads asking, "now what?"

The fastest way to resolve this error is to enable SMTP authentication for the email account.

1. The instant solution if ISP is blocking the sending of email ("If you can't beat them..."):
Change your "outgoing SMTP" setting to that of your ISP (ensure outgoing port is set to 25). If this is not possible see #2 below.

  • Call your ISP to get the latest SMTP settings for your area.
  • Once you change your outgoing email setting to that of your ISP your ISP becomes solely responsible for difficulties in sending email. Please contact them if you continue to have difficulties sending email using their service.
  • We've listed the most common settings below.
2. If you would prefer to not use your ISP's SMTP settings and like to continuing using "mail.my_domain.xxx" then try changing your outgoing SMTP port setting from 25 to 26. Click here to review how-to.
If after changing the port and restarting your email software you are still unable to send see #3 below.

3. Still unable to send after changing the outgoing SMTP port to 26?
Turn "SMTP Authentication" to "On."
You'll be required to enter your email address and password once again in the SMTP Authentication settings boxes. Click here to review how-to.

4. If all of the above fails it's possible your email software settings are corrupted in some way.
The solution to software error caching issues, that is, your email software reporting an error when an error does not exist on the server, is to delete the email account profile for your email address, quit your software, then restart your software and re-add your email account once again (the same as you did the first time you set up your email account on your computer).


Comcast is bouncing back my email with some odd error message about my using a residential IP address or some such. What can I do?

Try changing the port in your SMTP settings from 25 to 26.
Apparently Comcast has begun taking the drastic measure of blocking people who send email through port 25 (the Internet standard port for email).


Common question asked:
"I use a laptop and have a different ISP at home and at work, what can I do?"
About the only reliable, albeit annoying solution, is to set up multiple "personalities" in your email software. For example, name one work and another home.
Set the outgoing SMTP settings respectively.
When you wish to send email switch to the appropriate personality.


Some Common SMTP Settings:

Adelphia mail.adelphia.net
America Online (AOL) smtp.aol.com
AT&T (Broadband) mail.attbi.com
AT&T (Dialup) smtp1.attglobal.net
AT&T Worldnet mailhost.worldnet.att.net or imailhost.worldnet.att.net
Atlantic Broadband smtp.atlanticbb.net
BCPL mail.bcpl.net
Bellatlantic gtei.bellatlantic.net or smtpout.verizon.net
Bellatlantic.net smtpout.bellatlantic.net
Bellsouth mail.bellsouth.net
Bestweb smtp.bestweb.net
Blazenet smtp.blazenet.net
Cable One mail.cableone.net
CAIS smtp.cais.net
CAPU smtp.capu.net
Charm.net smtp.charm.net
Charter Communications smtp.charter.net
Comcast smtp.comcast.net
Compuserve smtp.compuserve.com or smtp.site1.csi.com
Concentric.net smtp.concentric.net
Covad smtp.covad.net
Cox Business smarthost.coxmail.com
Cox Central smtp.central.cox.net (central users)
Cox East smtp.east.cox.net(east coast users)
Cox West smtp.west.cox.net(west coast users)
Crosslink smtp.crosslink.net
DCANET smtp-relay.dca.net
Delmarva Online mail-gw.dmv.com
Delta Net smtp.deltanet.com
Direcway smtp.direcway.com
DSL Extreme smtp.dslextreme.com
Earthlink Network mail.earthlink.net or smtp.earthlink.net
Edge.net mail.edge.net
Enter smtp.enter.net
EROLS mail.erols.com
Ezy smtp.ezy.net
Flashcom mail.flashcom.net or smtp.flashcom.net
Frontline.net smtp.fcc.net
Gateway.net smtp.Gateway.net
GTI mail.gti.net
HotMail mail.hotmail.com
IBM.Global net smtp1.ibm.net
Interaccess.com smtp.interaccess.com
Internet America mail.airmail.net
ioNet Inc mail.ionet.net
ITOL mail.itol.com
Juno smtp.juno.com
MCI mailrelay.mciworldcom.net mailrelay.internetmci.com
Mediacom mail.mchsi.com
Mediaone.net smtp.ce.medione.net
MegaPath mail.megapathdsl.net
Mindspring smtp.mindspring.com
MSN smtp.email.msn.com
Nauticom mail.nauticom.net
Netcom smtp.ix.netcom.com
Netcom (Canada) smtp.netcom.ca
Netscape smtp.isp.netscape.com
NetZero smtp.netzero.net
NYU.edu smtp.nyu.edu
OLG.com mail.olg.com
OPTOnline Internet Service mail.optonline.net
Pacbell mail.pacbell.net
Patriot Media smtp.patmedia.net
Pipeline smtp.pipeline.com
Prodigy smtp.prodigy.net
PSI.net relay.smtp.psi.net
PTD.net promail.ptd.net port 25
QIS mail.qis.net
Qwest Internet Service pop.dnvr.qwest.net
RCN smtp.rcn.com
Rider.edu enigma.rider.edu
RoadRunner smtp-server..rr.com
SBC Global smtp.sbcglobal.net
SBC Global Yahoo smtp.sbcglobal.yahoo.com
Smallville Communications mail.toto.net
SNiP mail.snip.net
Spectrum DSL mail.webstable.com
SprintLink smtp.a001.sprintmail.com
Sprynet m6.sprynet.com
Starpower smtp.starpower.net
Sympatico mailhost.sk.sympatico.ca
UMBC smtp.gl.umbc.edu
US Internet smtp.usit.net
USA.NET mail.netaddress.usa.net
UUNet mail.uu.net
Verizon Internet Services outgoing.verizon.net or smtpout.verizon.net
Wide Open West smtp.mail.wideopenwest.com
XO Communications mail.njd.xo.com or smtp.concentric.net
Yahoo smtp.mail.yahoo.com
Ziplink smtp.ziplink.net


Properties ID: 000067   Views: 19483   Updated: 3 years ago
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