anytime I send an email with Thunderbird the program hangs while sending the message

Can you explain 'hangs' a little more detailed? What is your anti-virus software?

I've had this issue for over two years.

I do admire your patience.

Why hasn't the Mozilla team done something to correct this issue?

'Not responding' problems are almost always caused by anti-virus software. And many people do not seem to understand that scanning large mail files by anti-virus software takes time, and that scanning outgoing messages is absolutely useless.

Twoleftfeet asked a similar question in https://support.mozilla.org/en-US/questions/1070690 and did not reply.

Appears (s)he isn't really interested in assistance - or at least not on conversation

I'm using Windows 10. And I've tried Safe Mode several times without any improvement.

'

TwoLeftFeet said

I'm using Windows 10 64 bit and still anytime I send an email with Thunderbird the program hangs while sending the message and storing a copy. I've had this issue for over two years. Why hasn't the Mozilla team done something to correct this issue? I've found Support issues dating back several years talking about the same issue.

Support issues with slowness will go back to the first public build. Substitute the name of any software, but email clients in particular into your google search and you will see such complaints are not even limited to a single product.

You complaining about slowness on an operating system that had not been released two years ago. So I wonder what other things you brought from your old computer/operating system to your new. an anti virus product perhaps?

if you serious about engaging on this issue,please add the troubleshooting information to your post To find the Troubleshooting information:

• Open Help (or click on three-line-icon and select Help)
• Choose Troubleshooting Information
• Use the button Copy to clipboard to select all. Do not check box "Include account names"!
• Paste this in your post.

What causes a program to run slowly on a particular machine.is usually unique to the user and machine, although we do see some common reasons, like running McAfee or Avast anti virus, or not excluding the Thunderbird process from defender on Windows 10.

In replying to christ1: What is being scanned by the anti-virus program? If it is merely the outgoing message then I can attest to the fact that sending messages of no more than 100 characters can take as long as two minutes to send. The hangup is reported as "lookup", the "connect" then "send" with a % sign. Each of these events are extremely slow.

Looking up is Thunderbird querying your Domain Name Services (DNS) on your computer for the IP address of the mail server. This information is cached locally, but comes from an internet server This is the same thing that happens when you type goggle.com in the address bar of a web browser.

If you anti virus is not behaving properly. Or your DNS server is a slug, things go slowly. Interestingly, google will probably always go fast, as the give their cached information a long Time To Live (TTL) is once looked up it might ve quite a long time before that cached information goes stale. Email server often have very short TTL, so have to be looked up almost every time they are used. If you have security software that automatically cleans this DNS cache, or prevents it existing in the first place. Then your internet in general will be slower.

One thing you could try is changing your computers DNS server (most probably your ISP's to Googles which are 8.8.8.8 and 8.8.4.4 not I have no idea what operating system you use. So I suggest you google how to change the DNS servers.

The connect is where your anti virus gets in the way. In some cases entirely hijacking the connection and pretending to Thunderbird that the Anti virus IS the remote server in a man in the middle hack.

However a month ago you asked why Firefox was excruciatingly slow. You appear to have abandoned that question. Was it because you were asked to do something to diagnose you problem?

About the same time you asked about Thunderbird. I took a guess, even though it was about an unintelligible question. No response from you. Did I hit the mark or did you again loose interest because the answer did not suit you?

You appear to have much the same issues over and over. It is quite probably that your anti virus is the root cause of most of them.

Matt:

Thanks. I'm using Windows 10 Home. I've given up on Firefox because of the Untrusted Certificate problem, having tried all the suggested solutions. I'm convinced it's a bug and have reported it as such. So far, apparently noone has taken that one up.

As for antivirus, my only program is Defender and I use Reg Cure Pro several times a week to clean up. The Thunderbird font question was answered by the explanation that the scanned font may not have been Thunderbird compatible.

My Firefox connection is still considerably slower than the new Microsoft Edge and Google Chrome browsers to I have simply switched. However, I'm pretty much wedded to Thunderbird because of all the messages I've stored for different reasons. I use smtp-mail.outlook.com and smtp.googlemail.com as my two outgoing servers for the msn and gmail addresses. I'll check into changing DNS servers (by Googling it).

I've been seeing the same problem for some time. I used Mozbackup to move my profile from an XP system to a Windows 8 (now 8.1) system. One thing I can add to this discussion is that when the slowdown occurs, disk usage goes to 100% and stays there for 40 - 60 seconds or more. The slowdown is triggered by simply activating the currently running Thunderbird window (i.e., clicking on it after using another program. In other words, it has nothing to do with sending or receiving messages.

If I return to any other program, there is no slowness at all in them, but if I click back to TB, nothing happens. I may see an eventual response (such as the highlight moving to a different message after having clicked on it 10 - 20 seconds before that, and then it stops responding again. Meanwhile, disk usage continues at 100%.

 Application Basics

   Name: Thunderbird
   Version: 38.7.0
   User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0
   Profile Folder: Show Folder

             (Local drive)
   Application Build ID: 20160310150025
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory

 Mail and News Accounts
   account1:
     INCOMING: account1, , (none) Local Folders, plain, passwordCleartext

   account2:
     INCOMING: account2, , (pop3) mail.comcast.net:995, SSL, passwordCleartext
     OUTGOING: smtp.comcast.net:587, plain, passwordCleartext, true

   account3:
     INCOMING: account3, , (pop3) mail.ffez.com:110, alwaysSTARTTLS, passwordCleartext
     OUTGOING: smtp.comcast.net:587, plain, passwordCleartext, true

   account5:
     INCOMING: account5, , (imap) mail.ffez.com:143, alwaysSTARTTLS, passwordCleartext
     OUTGOING: mail.ffez.com:465, SSL, passwordCleartext, true

   account6:
     INCOMING: account6, , (pop3) mail.comcast.net:995, SSL, passwordCleartext
     OUTGOING: smtp.comcast.net:587, plain, passwordCleartext, true

   account7:
     INCOMING: account7, , (rss) Feeds, plain, passwordCleartext

   account8:
     INCOMING: account8, , (pop3) pop.googlemail.com:995, SSL, passwordCleartext
     OUTGOING: smtp.googlemail.com:465, SSL, passwordCleartext, true

   account9:
     INCOMING: account9, , (imap) imap.gmail.com:993, SSL, OAuth2
     OUTGOING: smtp.gmail.com:465, SSL, OAuth2, true

   account10:
     INCOMING: account10, , (pop3) mail.comcast.net:995, SSL, passwordCleartext
     OUTGOING: smtp.comcast.net:465, SSL, passwordCleartext, true

 Crash Reports
   http://crash-stats.mozilla.com/report/index/bp-7692155c-bcaf-499a-8537-731162160313 (03/12/16)
   http://crash-stats.mozilla.com/report/index/bp-62af95cb-90c1-4a7f-a8e2-3a8482160227 (02/27/16)
   http://crash-stats.mozilla.com/report/index/bp-1fcfcb5c-91cf-43c8-a25f-6bf452150712 (07/12/15)
   http://crash-stats.mozilla.com/report/index/bp-bff3e487-8f38-4fe0-976a-3adc42150601 (06/01/15)

 Extensions
   Lightning, 4.0.7, true, {e2fda1a4-762b-4020-b5ad-a41df1933103}
   Mailbox Alert, 0.16.4, true, {9c21158b-2c76-4d0a-980a-c51fc9cefaa7}
   Send Later, 4.4.4, true, sendlater3@kamens.us

 Important Modified Preferences

   Name: Value

     accessibility.typeaheadfind.flashBar: 0
     browser.cache.disk.capacity: 358400
     browser.cache.disk.smart_size_cached_value: 358400
     browser.cache.disk.smart_size.first_run: false
     browser.cache.disk.smart_size.use_old_max: false
     browser.display.background_color: #CCCCCC
     browser.display.use_system_colors: true
     extensions.lastAppVersion: 38.7.0
     font.internaluseonly.changed: false
     font.minimum-size.x-western: 10
     font.name.monospace.el: Consolas
     font.name.monospace.tr: Consolas
     font.name.monospace.x-baltic: Consolas
     font.name.monospace.x-central-euro: Consolas
     font.name.monospace.x-cyrillic: Consolas
     font.name.monospace.x-unicode: Consolas
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     font.name.serif.el: Cambria
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     gfx.blacklist.suggested-driver-version: 10.6
     gfx.direct3d.last_used_feature_level_idx: 0
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: 0ecacae2-2c09-4505-bb17-d84e16b9bc0
     mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false…
     network.cookie.prefsMigrated: true
     network.predictor.cleaned-up: true
     places.database.lastMaintenance: 1458233318
     places.history.expiration.transient_current_max_pages: 104858
     places.history.expiration.transient_optimal_database_size: 64381746
     plugin.importedState: true
     print.print_printer: Brother HL-5250DN series

• • Remainder removed due to lack of space **

jcarls said

I've been seeing the same problem for some time. I used Mozbackup to move my profile from an XP system to a Windows 8 (now 8.1) system. One thing I can add to this discussion is that when the slowdown occurs, disk usage goes to 100% and stays there for 40 - 60 seconds or more. The slowdown is triggered by simply activating the currently running Thunderbird window (i.e., clicking on it after using another program. In other words, it has nothing to do with sending or receiving messages.

To diagnose problems with Thunderbird, try the following:

• Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
• Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX

If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.

I don't know what to make of the results I'm seeing. I had tried the "disable your add-ons" a while back and saw no real difference. So I figured out how to start in Safe Mode with networking and worked with Thunderbird for about an hour. During this time, it responded with startling (to me) speed. Unfortunately, I could not run it that way forever, so I restarted, going back to normal operations.

Now the mystery: Thunderbird has worked perfectly for hours now, without any sign of the slowdowns I was experiencing. I have restarted the system in the past (in some cases, after complete power-down) and the problem persisted. The only difference I can see is simply running in Safe Mode (the first time I had ever done so on this system) and then returning to normal operations.