Connection to SMTP server Timed Out

User Help for Mozilla Thunderbird
Posts: 3
Joined: February 5th, 2010, 10:18 am

Post Posted April 16th, 2013, 4:05 am

I have been using Thunderbird for a few years now and it is great!

However, I have just set up a new account on it and this is using a "Private SMTP" server supplied by 34SP and am experiencing problems sending email through this server.

I am using the Mail Merge Add-on and have just tried to send 300 messages - it sends 20 or so OK, but, then I get the following message.....

The message could not be sent because the connection to SMTP server smtp.*************.org timed out. Try again or contact your network administrator.

Any ideas if this a Thunderbird issue or an SMTP server issue and any suggestions for how to investigate/resolve?


User avatar
Posts: 43932
Joined: July 30th, 2003, 5:06 pm

Post Posted April 16th, 2013, 7:20 am

Are you using that add-on to send a single message to 300 recipients or to send 300 individual messages? If the latter see what happens if you disable that feature.

I suggest you check what limits your email provider imposes on how many recipients you may send to during an hour. Gmail's smtp server for example imposes a limit of 100 recipients per hour if you use a email client (it has a higher limit for webmail). You might also want to ping your smtp server from a console window and see if it reports any data loss (poor quality connection).

I suggest you sign up for a free Gmail account, add it in Thunderbird, but then ignore it and configure your 34SP account to use the Gmail smtp server. The Gmail SMTP server will ignore whatever From: address you supply unless you add it in the Gmail web page at Setting -> Accounts -> "Add another email address". Once you do that try sending a message to about 50 people and see if it times out.

Run cmd from the start buttons edit field to create a console window.

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.


Pinging [] with 32 bytes of data:
Reply from bytes=32 time=56ms TTL=44
Reply from bytes=32 time=54ms TTL=44
Reply from bytes=32 time=55ms TTL=44
Reply from bytes=32 time=67ms TTL=44

Ping statistics for
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 54ms, Maximum = 67ms, Average = 58ms

Posts: 3
Joined: February 5th, 2010, 10:18 am

Post Posted April 17th, 2013, 5:20 am

Thanks for reply.

I am trying to send the same message to 300 different recipients.

We have signed up for a "Private" SMTP server with 34SP and this doesn't have a daily limit - just 20,000/year!

I am already using the GMail SMTP server for all my other accounts, so, I tried the same message through that. It processes 450+ before telling me I'd exceeded my daily quota!

Ping works fine and reports no data lost.

Am wondering if ought to try with Security set to None rather than SSL/TLS

Return to Thunderbird Support

Who is online

Users browsing this forum: Bing [Bot] and 5 guests