Fix slowness, crashing, error messages and other problems

Troubleshoot error messages on Thunderbird.

  • Fix problems with email providers (gmail, Yahoo, etc.) Learn how to fix problems with Gmail, Yahoo and other email providers
  • Error messages: what they mean and how to fix
  • Unblock Thunderbird from connecting to the Internet
  • Procedures to diagnose and fix problems
  • Thunderbird is slow or stops working
  • Thunderbird crashes
  • Why has my "Send" button been replaced with "Send Later" How to get back your "Send" button when it has been replaced by "Send Later"
  • IMAP Synchronization IMAP stands for the Internet Message Access Protocol. It enables a mail client (such as Thunderbird) to access messages stored on a mail server. It is more modern and fully featured than POP (Post Office Protocol), which is the other major protocol for accessing mail messages. Most email providers now support IMAP. To see whether your account uses IMAP or POP, check the Server Settings page in the Account Settings.
  • Cannot receive messages Troubleshooting information for if you are having problems receiving messages.
  • Cannot delete messages This article explains how to fix issues with message deletion caused by a corrupted trash folder.
  • Manual Account Configuration This article will show you how to manually configure the basic settings you need to send and receive emails with Thunderbird.
  • Sending and Receiving Messages on Thunderbird This article explains the sending and receiving functions in Thunderbird.
  • Rebuilding the Global Database The Global Database, Gloda for short, is part of the indexing system that enables the search function. Rebuilding the Global Database will initiate a re-indexing of emails and address book cards (newsgroup messages are not indexed).
  • Safe Mode TB '''Safe Mode''' is a special Thunderbird execution mode that can be used to troubleshoot issues in Thunderbird. In Safe Mode, you can reset some settings or disable add-ons that might be the source of problems. By comparing Thunderbird behavior in normal mode to its behavior in Safe Mode, you can find out if problems are being caused by a specific add-on.
  • Why does Thunderbird warn me that my server doesn't use encryption? This article explains why Thunderbird displays a warning if you set up an account which doesn't use encryption in order to protect your connection.
  • Plugin Crash Reports TB This article describes what happens when a Thunderbird plugin (such as Adobe's Flash player) crashes, and how Thunderbird crash reports are handled.
  • FAQ Changing IMAP to POP As of Thunderbird 3, the new [[Automatic Account Configuration]] Wizard can help you configure your connection to your email provider, but only if your provider is in Mozilla's database of Internet Service Providers or recognized by Thunderbird. While most of the large providers are included, many smaller ones are not yet in the account configuration database. If your mail server supports both IMAP and POP, Thunderbird will use IMAP by default. POP is also supported but must be manually configured using the following instructions
  • Configure Origin Address for Multiple Gmail Accounts Thunderbird can be used to manage multiple email accounts. These accounts can either be from the same or different email providers. However, when you have multiple Gmail accounts, by default Gmail will use your default account as the "From" and "Reply To" addresses. You must manually configure an alternate email address to be used as the "From" and "Reply To" values in messages.
  • Thunderbird can't be opened after you install it on a Mac - How to fix How to install Thunderbird on your Mac when you see this error: "Thunderbird can't be opened because the identity of the developer cannot be confirmed."
  • Configuring Email Aliases Instructions for configuring email aliases in Thunderbird using filters and identities
  • ISP Configuration Settings Each Internet Service Provider has a different set of configuration parameters for connecting to their email servers. A few of the most common connection scenarios are described in the pages accessed via the following links. The ISPs' websites and help pages are, however, the best source of connection information.
  • ISP Database Thunderbird version 3 tries to make things easier for users by enabling automatic configuration of the connection to their mail servers. Users provide their email account, user name and password, and then Thunderbird queries a database to find connection information for incoming and outgoing mail servers. This page gives instruction on how to add Internet Service Provider (ISP) configuration data to the database. It also describes the security mechanisms that prevent malicious entries in the ISP database that could put users at risk.
  • Mozilla Crash Reporter TB The Mozilla Crash Reporter sends crash information to a collection system when Thunderbird crashes. Thunderbird developers use this information to make future versions of Thunderbird crash less frequently.
  • FAQ AOL email Sent Folder As of February 2010, AOL email accounts no longer automatically store sent messages in Thunderbird's '''Sent''' message folder. However, you can manually configure Thunderbird to do this.
  • Small Resolution Screens Smaller devices (such as netbook and notepad computers) often have a screen resolution of 1024 x 600 or less. Thunderbird is not yet optimized to display at this resolution.