1. TechSpot is dedicated to computer enthusiasts and power users. Ask a question and give support. Join the community here.
    TechSpot is dedicated to computer enthusiasts and power users.
    Ask a question and give support.
    Join the community here, it only takes a minute.
    Dismiss Notice

Non-standard SMTP port

By NV30 ยท 21 replies
May 15, 2004
  1. So my ISP blocks port 25, and I don't think they'll open it up anytime soon. I downloaded Merak Mail Server and want to use it to run my own mail server. How can I get around this problem? Or is it impossible? Any messages sent from the server don't get through, and anything sent to it come back as "relaying denied". :(
  2. RealBlackStuff

    RealBlackStuff TS Rookie Posts: 6,503

    Don't know if this helps, check out the competition:

    Also, www.grisoft.com has a free Antivirus program AVG. For users of others than Outlook Express, there is a universal email-scanner (found under: avgemc483us.exe) which uses ports 9025 and 9110. Check it out.
  3. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    I think NV30 is having problems with his mail server, not a client.

    I dare to say that all semi-decent mail servers let you tell them what ports to listen on so the ISP blocking 25 is not a problem.

    The "relaying denied" message means that you have misconfigured your server. Most likely it came with tight security by default and you have to explicitly allow stuff to get through.
  4. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    Yes, just with the server. I'm not sure what options to use. I have ports 25, 366, 465 selected by default, and I tried to open ports 26 and 25 and then changed 25 to 26 in the server, but grc.com says that 25 is in stealth mode and that 26 is "unknown application" (?) I tried sending mail with port 26 selected, it just disappeared into the void of the Net.
  5. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    What are you trying to do here and what are you actually doing here?

    If you set up a SMTP server then it will accept mail from other computers via port 25 (or some other port) and either delivers it locally or relays it to some other SMTP server (the latter behaviour must be made very selective).

    You can send mail to the internet using any SMPT client (most e-mail clients are capable of working as SMTP clients). You don't need any open inbound ports to send mail to the outside world.

    Whatever you send to your SMTP server does not disappear into some void. Mail servers are built to keep all letters until a sucessful delivery or repeated failures. And everything is logged.
  6. Rick

    Rick TechSpot Staff Posts: 4,572   +65

    I agree with nodsu. If you are attempting to SEND mail, you do not need open ports.

    Something else may be wrong.
  7. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    I'm just trying to send and receive mail, but it just doesn't work. I've emailed Merak, hopefully they can help. Or it might just be my ISP.
  8. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    You don't need to run a server or install any special software besides a mail client (which you already have in the shape of "The Evil" Outlook Express). to send and receive mail. And it is unreal for an ISP to block outbound mail ports.

    You should check your mail program's configuration and firewall/security settings.

    A description what exactly you have done and are doing would help.
  9. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    No, sorry for not being clear. I have Outlook and can send/receive with my ISP's email, but now I want to run my own server so I can have more control over my email than what they give me. They do block port 25, sounds like you have to use their own SMTP server if you want to send out on 25.
  10. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    OK. All clear now.

    1: do you have your own domain name? If you don't then noone can deliver mail to your server. You can talk to your ISP or someone else about obtaining a subdomain or at least a host name and a mail relay to your server. Of course you can register a real second level domain name.

    2: Make sure that your server accepts mail from outside world only if the destination is in your domain. Most mail servers come out of the box with very strict settings and you have to explicitly allow things to happen.
  11. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    Hmm, no I don't have a domain name. I guess I should get one..
  12. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    Got a domain name now. So is it going to be possible now?
  13. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    Yes.. But you still have to get around the blocked SMTP port.

    I trust you have some idea about how e-mail works..

    There may be a way to get around the ISPs security. The easiest is to sign up to no-ip.com's mail reflector service but that costs money..

    Instead it may be that your ISP blocks port 25 only for sources outside their network.
    When you registered your domain name you had to fill in the MX records. These are the mail severs for your domain where your mail will get delivered. You list your own mail server as the primary MX and your ISPs SMTP server as the secondary.

    This way when mail is delivered to you the connection to primary server fails (since it is blocked) and the mail is sent to your ISPs server. The ISP server looks up the primary MX for your domain and tries to deliver the mail. Since this second attempt is from within the ISPs network it may work.
    This process is a tad slow though. Instant mail delivery won't be happening like this.

    You could also just call up your ISP and ask them nicely to open port 25 for you.

    If you do the setting up the server sotware by the manual (i'm sure there is some quick start guide) then it should work.
  14. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    OK, I'll try and do that. I registered a domain with 1and1 since they're cheap, and they gave me a fairly decent email plan, so I may just save myself some hassle and use them.
  15. Goalie

    Goalie TS Booster Posts: 616

    Ermm.. correction to Nodsu's statement.. you can route mail to SMTP addresses by ipaddress. The MX records are assumed on the lookup.

    For example, I can email myself from yahoo to me@

    Also, contact your ISP and ask them about hosting your own server, some ISPs are willing to make exclusion entries for those folks who ask (sometimes requiring a supplemental agreement)
  16. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    Hm. Now does that work for PPPoE where my addy always changes?
  17. Goalie

    Goalie TS Booster Posts: 616

    So long as you have people mail to whatever your IP address is, it'll work..

    but if you have a dynamic IP, you're really kinda hosed. Mail sent to an IP address goes to that IP address regardless of who's there.. so if you move out and someone else moves in, THEY would get the email.
  18. NV30

    NV30 TS Rookie Topic Starter Posts: 275

    Gah. Well I'll just stick with what I have then.
  19. qinzhi

    qinzhi TS Rookie

  20. Bukashaka

    Bukashaka TS Rookie

    Usually ISP's are blocking outgoing ports such as 25 etc. I found the simplest way to solve this - smtp.com. They are the oldest company, their service cost not much, they have professianal support staff. Since I've subscribed with them I haven't experienced any problems with sending email or they were resolved fast. I recommend you http://smtp.com
  21. patio

    patio TS Guru Posts: 482

    An 18 month bump...

    patio. :cool:
  22. Nodsu

    Nodsu TS Rookie Posts: 5,837   +6

    Nothing a determined spammer wouldn't do..

    I'll leave the post though.. Maybe someone is actually willing to pay for such a silly service.
Topic Status:
Not open for further replies.

Similar Topics

Add New Comment

You need to be a member to leave a comment. Join thousands of tech enthusiasts and participate.
TechSpot Account You may also...