Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Do you consider yourself a good problem solver? Try this one. Suddenly I can't send through smtp.gmail.com.

  • 10 replies
  • 2 have this problem
  • 1 view
  • Last reply by Lori

more options

Good day, everyone! I'm using TB 31.2.0, Windows 7 and FF 33.1. I have several email accounts, one of which is gmail. For years I've been using smtp.gmail.com to send email from TB for my gmail account with no problem. Two days ago I suddenly could no longer send from TB using smtp.gmail.com. The message I get is "Sending of message failed. The message could not be sent using SMTP server smtp.gmail.com for an unknown reason. Please verify that your SMTP server settings are correct and try again, or contact your network administrator."

Here's some more info:

1) I'm able to receive gmail in TB so apparently my username, password and security settings are correct. I'm using POP. 2) I haven't changed any of my settings (SSL/TSL and ports) prior to this problem. 3) I'm able to send and receive gmail from my iPhone and through gmail.com when using FF. 4) My daughter has a Google Education account on my TB and I'm able to send and receive gmail through her account. Her smtp is googlemail.com. I tried changing my account to that but it still didn't work for my account. 5) I've tried telnetting to gmail.smtp.com and it works fine. 6) I tried changing ports to all of those suggested by google and none of them work. 7) I have Less Secure Apps enabled on my google account.

To sum it up, everything was working fine until 2 days ago. I can send and receive gmail through FF and iPhone. I can receive gmail through TB but I can't send gmail through TB.

I've posted in the gmail forum and no one there can think of anything yet.

Please help? If you can figure out this one I will nominate you for Problem Solver Of The Year!

Good day, everyone! I'm using TB 31.2.0, Windows 7 and FF 33.1. I have several email accounts, one of which is gmail. For years I've been using smtp.gmail.com to send email from TB for my gmail account with no problem. Two days ago I suddenly could no longer send from TB using smtp.gmail.com. The message I get is "Sending of message failed. The message could not be sent using SMTP server smtp.gmail.com for an unknown reason. Please verify that your SMTP server settings are correct and try again, or contact your network administrator." Here's some more info: 1) I'm able to receive gmail in TB so apparently my username, password and security settings are correct. I'm using POP. 2) I haven't changed any of my settings (SSL/TSL and ports) prior to this problem. 3) I'm able to send and receive gmail from my iPhone and through gmail.com when using FF. 4) My daughter has a Google Education account on my TB and I'm able to send and receive gmail through her account. Her smtp is googlemail.com. I tried changing my account to that but it still didn't work for my account. 5) I've tried telnetting to gmail.smtp.com and it works fine. 6) I tried changing ports to all of those suggested by google and none of them work. 7) I have Less Secure Apps enabled on my google account. To sum it up, everything was working fine until 2 days ago. I can send and receive gmail through FF and iPhone. I can receive gmail through TB but I can't send gmail through TB. I've posted in the gmail forum and no one there can think of anything yet. Please help? If you can figure out this one I will nominate you for Problem Solver Of The Year!

All Replies (10)

more options

Have you checked your firewall settings to be sure it is not blocking Thunderbird.

more options

Yes, I checked the firewall. I disabled it and TB still couldn't connect to smtp.gmail.com in that one account.

more options

Maybe you should post your troubleshooting info and see if someone spots a problem with your settings.

You can do this from the Help menu.

more options

Here's my troubleshooting info:

(Account 9 is my gmail account. Account 20 is my daughter's Education gmail account.)

 Application Basics
   Name: Thunderbird
   Version: 31.2.0
   User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0
   Profile Folder: Show Folder
             (Local drive)
   Application Build ID: 20141012121702
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory
 Mail and News Accounts
      account9:
     INCOMING: account9, , (pop3) pop.gmail.com:995, SSL, passwordCleartext
     OUTGOING: smtp.gmail.com:465, SSL, passwordCleartext, true
   account20:
     INCOMING: account20, , (pop3) pop.gmail.com:995, SSL, passwordCleartext
     OUTGOING: smtp.googlemail.com:465, SSL, passwordCleartext, true
more options

If you access gmail using a phone and a computer, then it may be to do with gmail.

You would need to set up 2 step verification for the phone and then generate an 'application specific password' for use in Thunderbird.

See info:

more options

Toad-Hall, thank you for your response. But I've been accessing my gmail account with both my computer and phone for years without any issue. And my daughter accesses her account with a computer and phone with no problem.

Doesn't it seem strange that my access to smtp.gmail.com would suddenly change, without any change to my pop access? Regardless of 2 step verification?

I have also posted in the Google Help forum and there doesn't seem to be any issue about not having 2 step verification yet, although they did suggest that I set it up in the future.

more options

If you do not set up 2 step verification then you need to select that you want to use what gmail call 'Less secure apps'. https://support.google.com/accounts/answer/6010255?hl=en

And yes, gmail/google have made these recent changes.

update...sorry just noticed you already stated you have this selected.

Modified by Toad-Hall

more options

Toad-Hall, I've had Less Secure Apps enabled all along.

more options

In Account Settings > Outgoing Server(SMTP) Confirm you tried: Port: 587 Connection Security: STARTTLS

What Anti-Virus/firewall product are you using? In your Anti-Virus/firewall product, Thunderbird should be to 'Allow'. Sometimes if the Anti-Virus/firewall product updates or Thunderbird updates, then Anti-Virus/firewall product seems to not realise this. so you have to disallow close and reopen and then select 'Allow again.


According to downrightnow website, the last major disruption reported on gmail was two days ago; which seems to coincide with your issue starting.

Also, just had a thought. Maybe this could have something to do with your IP address and gmal not liking it for some reason. Could you reboot the router/hub to see if it selects a different IP address.

more options

Yes, I tried STARTTLS and Port 587.

I'm using Norton Internet Security and TB is set to Allow.

As for the IP address, I'm using the same one when I check my gmail inbox and when I send and receive with my daughter's account and they all work fine. Would gmail like my IP for some functions but not others?