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SMTP Problems

  1. Feb 6, 2005 #1
    I have a POP3 email account. I have a laptop and receiving email is no problem for me where ever I go. However sending email is. When I send my email from home I have no problems. But when I go to a friend's house and use their connection it fails to connect to the SMTP server. From this I can only guess two things. Either my friend has some port blocked that SMTP needs or my connection needs to be through my ISP for SMTP to work. The blocked port makes more sense to me on it's face however I doubt all my friends have this port blocked

    I noticed this same problem when I had two ISP at home a long time ago. I had AOL and Netzero. When receiving POP3 mail I had no problems. However sending mail from my @netzero.com account was only possible when I connected to netzero.

    Can someone clear this up for me?
  2. jcsd
  3. Feb 6, 2005 #2


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    It's typical of most ISPs to allow SMTP access to their netblocks only. This would explain why you can only use your ISPs SMTP server when you use their Internet connection.

    What you're trying to do is called `relaying.' Normally, if you were on your ISP's netblock, this wouldn't be a bad thing; however, limiting SMTP access to their netblocks only, prevents spam.
  4. Feb 6, 2005 #3


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    Also, if your ISP has any sort of webmail, this would allow you to send/receive emails through their SMTP/POP3/IMAP servers. The only downside is that you wouldn't be able to use the email client that you typically use.
  5. Feb 6, 2005 #4
    Thanks. At least I know what the problem is now. I can send email from the same address but from the web instead. It's just annoying to compose email on my fancy program and not be able to use it. But if it cuts down on spam than i'm ok with it.
  6. Dec 22, 2007 #5
    Except identifying, the problems are supposed to be resolved :) I am using smtp server from http://smtp.com, for a few bucks per month I was able to set my outbound at laptop and configure iPhone to their server as well.
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