Sending email from Thunderbird very slow

[ao1]

Hello,

When sending email from Thunderbird, it consistently takes 30 seconds to connect to the SMTP server. This is extremely annoying.

Log excerpt:

2019-02-06 17:25:10.693000 UTC - 1376[3a10140]: SMTP Connecting to: mail.messagingengine.com
2019-02-06 17:25:40.795000 UTC - 1376[3a10140]: SMTP entering state: 0

The same delay happens whether I use mail.messagingengine.com or smtp.fastmail.com

Any ideas?

Edit:
telnet mail.messagingengine.com 465 connects instantaneously

[n5bb]

It appears that you are using the old SMTP server and have not switched to using the current smtp.fastmail.com server on port 465 with an app-specific password. See:
https://www.fastmail.com/help/techni...sandports.html

With the current recommended settings I get connections in under 1/2 second. Here are logs showing the start of two message send sessions using Thunderbird 60.5.0:

2019-02-08 07:48:19.216000 UTC - [53908:Main Thread]: I/SMTP SMTP Connecting to: smtp.fastmail.com:465
2019-02-08 07:48:19.479000 UTC - [53908:Main Thread]: I/SMTP SMTP entering state: 0
2019-02-08 07:48:19.479000 UTC - [53908:Main Thread]: I/SMTP SMTP Response: 220 smtp.fastmail.com ESMTP ready

2019-02-08 07:59:16.889000 UTC - [43800:Main Thread]: I/SMTP SMTP Connecting to: smtp.fastmail.com:465
2019-02-08 07:59:17.249000 UTC - [43800:Main Thread]: I/SMTP SMTP entering state: 0
2019-02-08 07:59:17.249000 UTC - [43800:Main Thread]: I/SMTP SMTP Response: 220 smtp.fastmail.com ESMTP ready

I am located in the Dallas, Texas, area and using a FIOS high speed fiber optic connection to my Frontier ISP.

Bill

[gj15]

This could be symptomatic of your IP address having a reverse DNS problem, discussed towards the end of this thread: http://www.emaildiscussions.com/showthread.php?t=72258

[n5bb]

Originally Posted by gj15

This could be symptomatic of your IP address having a reverse DNS problem, discussed towards the end of this thread: http://www.emaildiscussions.com/showthread.php?t=72258

That’s a good possibility. The Fastmail SMTP server has to do several things before the SMTP transactions used to send a message begin:

• The preferred server is smtp.fastmail.com over port 465 (SSL/TLS must be activated, but not STARTTLS). The client and server must negotiate the SSL/TLS connection, but usually this is very fast.
• The client IP address must be accepted. There are block lists for known insecure IP addresses.
• If the IP looks suspicious (such as not resolving to a reverse DNS), the connection can be greylisted. This will defer the connection with a delay. The client will retry and eventually get connected.
• Authentication using an application password must be completed.
• The SMTP server reports that it is ready to accept commands. This is where the email transfer occurs.

Bill

[ao1]

I got a reply from FM's tech support. It's a reverse DNS issue, I'll have to take it up with my ISP.