Thunderbird

Thunderbird is a free e-mail client that allows users running Microsoft Windows, macOS, Linux, and other supported systems to send, receive, and manage their e-mail. Thunderbird is a free email application that’s easy to set up and customize – and it’s loaded with great features!

Official Thunderbird website: https://www.mozilla.com/thunderbird/

When AOL (Netscape’s parent) scaled back its involvement with Mozilla organization, the Mozilla foundation was launched on July 15, 2003 to ensure Mozilla could exist without Netscape.

 Contact information

Thunderbird, developed by Mozilla Corporation is a free, open-source app that allows managing emails, chats, news feeds, and newsgroups quite efficiently. It is a desktop based application that gives complete control and extensive ownership over the email messages. Despite having numerous benefits, there are some errors and issues that require timely troubleshooting. 

Let’s look at each and their possible solutions: 

#1: Cannot Delete Messages

The reason behind the inability to delete an email message in Thunderbird could be a corrupt trash folder. To resolve this, follow the steps below:

1. Open the Profile folder by clicking on the Menu button from the top right of the Thunderbird window. Select Help and click on Troubleshooting Information. In the then appeared Troubleshooting Information tab, click on Show Folder button available under Application Basics. The windows will display the profile files.
2. Next, close the Thunderbird application
3. In the File Manager, open Mail folder or Imap Mail folder (as per POP or IMAP account you are using)
4. Open the folder with the incoming mail server name (such as imap.googlemail.com or pop.googlemail.com)
5. Select Trash and msf files and erase them. In several accounts, this file is named Deleted or Bin
6. Then, restart Thunderbird

• In the case of IMAP, a new Trash folder will automatically be generated by Thunderbird.
• In a case of POP, go to the Folder List and then right-click on the account name and select New Folder. Next, provide the folder name as Trash and click on Create Folder to confirm 

In case the problem continues and you fail to delete the email messages that are no more required, you can select an alternate option to switch the emailing app to MS Outlook which is comparatively proficient and organized. To utilize MS Outlook, you will need to move all the data from MBOX to PST files.

#2: Unable to send Email Messages

If you are unable to send email messages from your Thunderbird account, there can be two reasons behind this:

• Inappropriate Thunderbird Settings
• Blocked Port 25 by ISP (Internet Service Provider)

To resolve this issue:

1. Ensure that Thunderbird Settings are appropriately configured

• Incoming mail server (POP3/IMAP server): mail.yourdomain.com
• Outgoing mail server (SMTP server): mail.yourdomain.com
• Username: the full e-mail address like email@yourdomain.com
• SMTP authentication must be enabled for the login to be successful.

2. Try using alternative TCP port 2525 for SMTP Server. 

Note: If you fail to rectify this issue, you can convert emails and other components from MBOX to PST file format for utilizing smooth functionality of MS Outlook.

 #3: Cannot Receive Messages

If the Thunderbird account fails to receive messages, check whether the account is configured correctly. To check settings for Thunderbird account:

1. Select Tools and then click on Account Settings
2. From the list that appears on the left pane, select Server Settings
3. You can see the configuration settings at the top of the page to verify the connection to the incoming mail server
4. The email account provider gives you connection information about the servers. Ensure that the account settings match these settings. 

#4: Thunderbird Closes Unexpectedly

When Thunderbird exits unexpectedly, the situation is referred to as application crash. When it closes suddenly, Mozilla Crash Reporter appears. Numerous reasons are responsible for the crash: therefore, the best way would be to post-crash report ID.

Alternatively, attach a stack trace in the bug report or any forum. This will help rectify the actual reason. Exporting data from Thunderbird to PST format will help rectify the persisting issue and achieve continued functionality. 

#5: Thunderbird warns that the Server doesn’t use encryption

First of all, verify if the server supports encryption. If it does then you may require changing Thunderbird settings. Click on the Change Settings button and implement correct settings

If the mail Server doesn’t support encryption, then, you may use it at your own risk. Check the box associated to I understand the risk and click on Create Account button. Alternatively, switch to mail service provider that offers a secure connection such as Yahoo, Gmail, etc. 

#6: Start Thunderbird in the Safe Mode

You can start Thunderbird in the Safe Mode to troubleshoot persisting issues and error. In the Safe mode, you can reset Thunderbird settings or disable the add-ons that are creating issues. To verify if the problem is being caused by a specific add-on, try comparing application behavior in Normal mode to that of the behavior in Safe mode.

1. To start Thunderbird in Safe mode, follow the steps below:

• When Thunderbird is not running: Press and hold down the Shift key while starting Thunderbird to open it into Safe mode
• When Thunderbird is running: Click on the Help menu from the top of Thunderbird window and then select Restart with Add-ons Disabled… menu item. Next, click Restart button in the dialog box

2. In the then appeared Thunderbird Safe Mode dialog box, Click on Continue in Safe Mode button to accomplish task to start Thunderbird in Safe Mode 

#7: Create Email Alias

An email address that forwards messages to another email account is referred to as the alias. Once you set-up email alias, you can freely configure Thunderbird for downloading and sorting messages to the alias account. The messages are received in the same manner they are received in the primary account.

The example specified herein will explain the procedure to configure Windows Live Mail or Hotmail account to send messages to the email alias in your Inbox.

1. Sign in with Hotmail account, click on Options and then select More Options.

2. Under Customizing Hotmail, click on Rules for sorting new messages to configure the way in which messages are sorted.

3. Delete the rule that specifies to place the new email messages into its own folder.

These are some of the issues and errors that appear frequently in Thunderbird and affect the performance as well as the functionality of the application. In order to avoid such errors, you can use any alternate emailing client such as MS Outlook. The desktop based emailing program is efficient enough to offer responsive features and function. 

Not Able To Send Or Receive Emails On Thunderbird:

There are a variety of possible reasons why you may not be able to send or receive emails.

Incorrect Password: Please verify your web-mail, and if your web-mail is not functioning as it should, then it’s likely a problem with the password. In this scenario, call your Internet service provider to resolve it.

Wrong server info: Please verify the settings of your incoming and outgoing server along with the port numbers to make sure that they are correct. If your webmail is functioning as it should and your server settings are correct, then it’s an issue with Mozilla Thunderbird.

Problem 1: Thunderbird Cannot Delete Messages

If a user is not able to delete an email message from Thunderbird, then the most common reason is corrupt trash folder. To Fix Thunderbird Problems , follow the mentioned below steps:

1. To start the process, open your Profile folder
   2. After that, click on the Menu icon from the top right corner of the Thunderbird window.
   3. Then, choose Help option >> Troubleshooting Information option from the displayed list. After that, a Troubleshooting Information tab will open. Click on the Open Folder button under the Application Basics tab. It will display all the files of that profile
   4. Now, you can close and exit the Thunderbird application
   5. Then, from the File Manager, you need to open Mail folder or Imap-Mail folder (based on the POP or IMAP account a user is using)
   6. After that, you can open the folder with that has incoming mail server name (like imap.googlemail.com or pop.googlemail.com)
   7. Now, choose the Trash and MSF files and delete all of them. In some of the accounts, it is named as Deleted or Bin
   8. Restart the Mozilla Thunderbird Application
   If you are using an IMAP account, a new Trash folder is created automatically by Thunderbird.
   If you are using POP account, then move to the Folder List >> right-click on account name >> choose New Folder. After that, you can give a name to the folder i.e. Trash and hit Create Folder button to confirm

After following all the steps above to Fix Mozilla Thunderbird Error, if a user is still not able to delete the email messages, then it suggested to migrate to some other email application like Outlook. However, to make use of Microsoft Outlook, a user need to convert MBOX file data to PST format in order to solve Mozilla Thunderbird email issues

Problem 2: Thunderbird unable to send email messages

Another common problem faced by the users is Thunderbird is unable to send emails. There can be two possible reasons behind it:

Improper Settings of Thunderbird

ISP has Blocked Port 25

Now, to Fix Thunderbird Problems, a user can follow the steps mentioned below:

1. First of all, make sure that Thunderbird Settings are configured in a proper manner

Incoming mail server (POP3/IMAP server): mail.your_domain.com

Outgoing mail server (SMTP server): mail.your_domain.com

Username: the complete email ID such as email@your_domain.com

To have a successful login, SMTP authentication must be enabled

2. After checking all above, try to use an alternative TCP port 2525 for the SMTP Server.

Problem 3: Thunderbird cannot receive Email Messages

It might also be possible that Thunderbird account is unable to receive any messages & Thunderbird not showing emails, so to make sure that account is configured properly. To do the same, follow the steps mentioned below to resolve Mozilla Thunderbird email issues:
1. Click on Tools >> Account Settings Option
2. Now, choose the Server Setting option from the list displayed in the left pane
3. After that, check the Configuration Settings from the top of the page and make sure the connection with the incoming mail server
4. Here, this email account provider will provides you the connection information related to the servers. After that, make sure the account settings are matched to these settings

Problem 4: Thunderbird Closes Unexpectedly

When Thunderbird terminates unexpectedly, it results in application crash. However, if there is a sudden shutdown, Mozilla Crash Reporter displays. There can be various reasons, which are responsible for the crash. So, to fix Thunderbird Problems, the best approach is to post-crash report ID.

If this does not work, you can attach the stack trace in your bug report or in any forum. This will help in resolving the actual cause.

Problem 5: Warning- Server doesn’t use encryption

Before doing anything, make sure that the server supports encryption. It is because if it does not support, then a user needs to change the Thunderbird settings. For this, click Change Settings button and apply correct settings

If it does not support encryption, then a user has to use it at his or her Own risk. To do this, first of all, check the box corresponding to I understand the risk and then, click on Create Account button. Another way is, move to the mail service provider, which provides a secure connection like Yahoo, Gmail, and much more.

Start Thunderbird in Safe Mode & Fix Thunderbird Problems or Errors

To troubleshoot any persisting Mozilla Thunderbird email issues, a user can start the Thunderbird in the Safe Mode. It is because a user can change the Thunderbird settings in the safe mode. If required, one can disable add-ons also, which creates Thunderbird issues. In order to make sure that the problem is because of a specific add-on, a user can compare the application behavior in Normal mode and in Safe mode.

1. 1. To begin the Thunderbird in Safe mode, perform the following steps:

If Thunderbird is not running: you can press & hold the Shift key and open Thunderbird in a safe mode.

If Thunderbird is running: Go to the Help option from the Menu and choose Restart with Add-ons Disabled… option. After that, click on the Restart button from the dialog box
2. After that, a dialog box appear for Thunderbird Safe Mode, you just need to click on Continue in Safe Mode button to begin the Thunderbird in Safe Mode

As discussed above there are many issues and Mozilla Thunderbird Errors that a user keeps on encountering on the frequent basis. Therefore, to avoid all such Thunderbird issues permanently, a user is advised to switch to some other email client such as MS Outlook. It is also one of the most efficient emailing programs with many responsive features and function.

The Bottom Line

Considering all the problems discussed above related Thunderbird, a user is advised to switch to MS Outlook. Now, to fix Thunderbird Problems & Issues, a user is migrating towards Outlook. Therefore, to perform this migration successfully, a user is advised to use SysTools MBOX to PST converter and move all Thunderbird mailboxes to MS Outlook in just a few numbers of clicks.