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Cannot Send Emails From Thunderbird, How Do I Fix It?

  • 7 replies
  • 1 has this problem
  • 10 views
  • Last reply by Matt

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I was sending & receiving fine for a long time. All of a sudden on Thursday afternoon, 112/09/15, I couldn't send. When I tried, it said the server timed out. Then, I couldn't receive either.

Well today, I was able to correct the receiving part. My domain provider/email provider, Hostgator had me change the incoming port. to 993. That worked. However, it is weird because that is what it was originally when the problem happened. Later in trying to fix it, I changed it to 995. Now when support has me put it back to 993 I can receive again.

Anyway, the send still doesn't work. Everything is working on Hostgator's side. So they said it's a problem with Thunderbird. We tried changing the send port to 587 from 465. That didn't help.

The email address I am having trouble with is on the domain myemailaddress.biz It is hosted with Hostgator.

My ISP: Time Warner Roadrunner

Not sure if I have a firewall or antivirus.

OS: Windows 10

Thunderbird is 38.4.0

Screenshot of Tbird SMTP settings is attached. Thanks.

I was sending & receiving fine for a long time. All of a sudden on Thursday afternoon, 112/09/15, I couldn't send. When I tried, it said the server timed out. Then, I couldn't receive either. Well today, I was able to correct the receiving part. My domain provider/email provider, Hostgator had me change the incoming port. to 993. That worked. However, it is weird because that is what it was originally when the problem happened. Later in trying to fix it, I changed it to 995. Now when support has me put it back to 993 I can receive again. Anyway, the send still doesn't work. Everything is working on Hostgator's side. So they said it's a problem with Thunderbird. We tried changing the send port to 587 from 465. That didn't help. The email address I am having trouble with is on the domain myemailaddress.biz It is hosted with Hostgator. My ISP: Time Warner Roadrunner Not sure if I have a firewall or antivirus. OS: Windows 10 Thunderbird is 38.4.0 Screenshot of Tbird SMTP settings is attached. Thanks.
Attached screenshots

All Replies (7)

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We tried changing the send port to 587 from 465. That didn't help.

There is no point trying arbitrary combinations of 'Connection Security' (none, SSL/TLS, STARTTLS) and 'Port' (25, 465, 587). Simply set what's required by your email provider. It's their server, and they know what the correct settings are. So check with them, or look up the email server settings on their support home page. Once you have the confirmed settings and it still doesn't work come back here to ask.

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My email provider, Hostgator, was the one that told me to try port 587. They said it should be either 465 or 587. It was on 465. We tried 587. It didn't help.

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There is more than just the port number which needs to be set correctly. See https://support.mozilla.org/en-US/questions/1098633#answer-816922 (replaced incorrect link)

Modified by christ1

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I don't see anything at that link (https://support.mozilla.org/en-US/user/christ1) except a couple of badges.

I spoke to tech support again. They said the best security setting is none. That didn't solve the problem.

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I don't see anything at that link

Sorry, that was supposed to be https://support.mozilla.org/en-US/questions/1098633#answer-816922

I spoke to tech support again. They said the best security setting is none.

That would typically require port 25 then. But if SSL/TLS and port 465 did work before, why would 'none' be the best now? Doesn't make sense to me. If 'none' really is what they need, find a new provider. 'None' means everything is sent in the clear. Perhaps they just had a server glitch, and SSL/TLS and port 465 now works again? But as said before, there is no point guessing.

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Well, nothing has helped. Hostgator can't help. They say everything works fine on their end. It works fine for me too when I login online and use Squirrel Mail.

The only time it doesn't work is when I use Thunderbird. Even that used to work. Why it doesn't now is the question. But since I can send emails when I login online, it seems that the problem lies with Thunderbird. Question is, what is the problem and why did it develop out of the blue after it had been working fine for many months?

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If your using an anti virus program other than Defender, turn of email scanning. if you are using defender remove Thunderbird from the processes it monitors.