Mail SMTP Server Not Connecting.

Ryfus wrote:

My ISP is Mediacom, and I'm using a Mediacom email address. I can successfully ping the mail.mediacombb.net SMTP server, and I can also use Mediacom webmail without a problem.

New issue. I haven't changed anything...all was working on Monday and Tuesday, and I simply woke up Wednesday morning and none of my devices will connect to Send email - none of my Macs, iPads, nothing. Reported to Mediacom and all they did was to tell me to call Apple. So I spent a couple hours on the phone with Apple Support this afternoon and stuumped them too...they are going to call me back tomorrow.

outgoing mail is <smtp.mediacombb.net>

I get no ping>>Timeout all the way

MacBook-Pro ~ % ping smtp.mediacombb.net

PING mcc.smtp.a.cloudfilter.net (35.172.131.32): 56 data bytes

Request timeout for icmp_seq 0

Request timeout for icmp_seq 1

Request timeout for icmp_seq 2

Request timeout for icmp_seq 3

Request timeout for icmp_seq 4

Request timeout for icmp_seq 5

Request timeout for icmp_seq 6

Request timeout for icmp_seq 7

Request timeout for icmp_seq 8

Request timeout for icmp_seq 9

Request timeout for icmp_seq 10

Request timeout for icmp_seq 11

Request timeout for icmp_seq 12

Request timeout for icmp_seq 13

^C

I would contact Mediacom support— if it is a server issue it is beyond your control or Apple control.

You have to rule out an issue on their end.

front line telephone support is typically tier 1, you need to escalate the issue up the chain of command

Mediacom/Customer service

1 (855) 633-4226

Contact Us - MediacomCable – Mediacom Communications

https://support.mediacomcable.com/#!/Log/In?redirect=Account-%7B%7D

If in doubt search the developers website or contact: Support/Help/FAQ/Known issues/compatibility/Updates

https://mediacomcc.custhelp.com/app/answers/list/kw/SMTP%20server%20issue/page/1

https://downdetector.com/status/mediacom-communications/

Ryfus wrote:

I can't use anything but webmail if I can't connect to an SMTP server to be able to Send email - I do have a GMail account, and have tested it with my clients. I can't log into the GMail SMTP server from my computer or iPads either - only using a browser, and not with any of my machine clients.

to review:

neither of my 2012 Mac Mini or 2018 Macbook Pro running Catalina, nor my 2009 Macbook Pro running Snow Leopard will connect to my SMTP Server...

If this is the same email, same SMTP does it not paint a picture it is not your issue but a SMTP issue...

Verify you have turned off any VPN, on board Firewall, third party anti-virus, Hide IP address features in Mail, safari etc...

Hard to believe across the board on all 3 computers you have a simultaneous failure— SMTP port configurations do not typically change them selves

Delete the account and set it up as new if no change anywhere and no support.

Remove email accounts in Mail on Mac - Apple Support

To trouble shoot further you can:

—Test issue in another user (or guest user) account Set up users, guests, and groups on Mac - Apple Support

  This will tell you if it a universal issue or isolated to your user/admin account. 

 —SafeBoot How to use safe mode on your Mac - Apple Support will sort many anomalies

Takes a bit longer to get to the login screen, does a quick disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, font cache, etc. 

Login and test. Reboot  as normal and test.  Caches get rebuilt automatically.

In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc impacting the  smooth operation, however a  reboot will put it back to normal mode

This test will tell you if third party interference; extensions etc are not loaded in safe boot mode. 

Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS

Add email accounts in Mail on Mac - Apple Support

Add email accounts in Mail on Mac - Apple Support

Note—

IMAP accounts stay on the server, so no local loss, when you re-sync

POP accounts download and remove from the server—therefor save your inbox/sent box if you want them

"On My Mac" is just that, local folders you created and moved mail into. So no loss

sorry I could not help you resolve your issue

Do a hard shut down of your router and modem and reboot both to test

ref: .mediacomb says SMTP port

Outgoing smtp.mediacombb.net 587

gmail uses the same port

smtp.gmail.com Requires SSL: Yes Requires TLS: Yes (if available) Requires Authentication:

Yes Port for SSL: 465

Port for TLS/STARTTLS: 587

ref:

TCP and UDP ports used by Apple software products - Apple Support

With an AppleID you have a @icloud mail account set that up and test. It appears to use port 587 as well.

iCloud Mail server settings for other email client apps - Apple Support

if you get an issue here on iCLOUD—contact Apple Support and escalate the issue up the chain of command

Call Customer Support  (800) MY–APPLE (800–692–7753)

If you have cell provider for an iPhone/android different than your mediacomb then compare your results using cellular data only to send email as a test. This may be telling and would point back to your ISP as the issue.

If the router is suspect replace it.

Ryfus wrote:

Yes...I've gotten past the bot, and talked to an actual tech twice. Mostly they just want to blame Apple.

Get a different email. gmail is free. Log into your Mediacom and set up automatic forward to your new email address and use that.

Ryfus wrote:

• As of about two days ago, none of my Macs will connect to my SMTP Server using Apple Mail - neither of my 2012 Mac Mini or 2018 Macbook Pro running Catalina, nor my 2009 Macbook Pro running Snow Leopard will connect to my SMTP Server...so I cannot Send email, but I can still Receive incoming email.

Connection Doctor indicates red dot; "server Offline" - but I can successfully ping the Server and use webmail to both Send and Receive.

So it appears to be something at my end, but to happen across three machines all on the same day at the same time? How can I fix?...

Ryfus

You do not say who is your Mail provider?

Sounds like a Server issue if all devices are failing. Server issues are beyond your control.

you are using the Mail.app as you client are you saying your email is provided by @iCloud.com (?)

if so check the server:

Apple - Support - System Status

You can always wait and try later...and see if the issues sorts itself.

Quit Mail and relaunch it holding the Shift key and compare your results.

old issue, new issue, what changed?

here are a few possibilities:

Ryfus, we're experiencing trouble too, and it sounds very similar to your issue. What makes this so hard to troubleshoot, is that there seem to be multiple factors. I have tested different devices, networks, DNS servers, SMTP ports, apps, and mail accounts. If I switch from our broadband network (over wi-fi) to my mobile hotspot, I can send just fine. I can send from my iCloud account, but not my own mail server. And like you, I can successfully connect to my mail server from Terminal (using ping and netcat utility) and I can send via webmail. So, the common factors seem to be:

1. Our broadband network (we're on Satellite NBN in Australia)
2. My own mail server
3. Apple Mail client.

I manage my own mail server, so I can go in and check logs. There are no logs indicating a failure to authenticate from my IP, so I'm left scratching my head. I'll keep working on it and let you know if I have any success!

Hey Ryfus. This may not help you, but I finally fixed our problem by rebuilding Exim (mail transfer agent) on our mail server. Strange that it was only affecting us when accessed from a certain network, which is what threw me, but in some ways I'm not surprised… Exim can be a little flaky at times!

Good luck solving your issue!

Ryfus wrote:

Yes - that is exactly what I thought, but they are not really being cooperative. I do have a Trouble Ticket in...

As an aside...I just tried swapping out a router (my Apple Airport for an Airport Express that I travel with)...no change.

Maybe tomorrow it will be back up and running

smtp.mediacombb.net

--- mcc.smtp.a.cloudfilter.net ping statistics ---

29 packets transmitted, 0 packets received, 100.0% packet loss