When the free email client Mozilla Thunderbird slowly is that can have various causes. We present the three Commonly and give tips on what to do about it. If you have not the latest version of the free e-mail and feed reader program, you can download the current Thunderbird here.

Thunderbird slowly - causes and solutions

Thunderbird slowly

The three most common causes include the following:

  • Overcrowded Inbox
  • Plug-in works or stops responding
  • defects Gloda

1. Overcrowded Inbox

PROBLEMThunderbird stores by default all incoming e-mails in a file, the INBOX. The more full the INBOX, the slower the reading and searching in this file, especially when mails with large attachments.

SOLUTION: By creating subfolders can reduce the INBOX and thus increase the performance again. Older e-mails should move into new subdirectories or - deleted - unless they are no longer needed.


  • A new subfolder is created by right-clicking on the Inbox folder. Then select the new dialog window, select the "New Folder ..." from. Then you can the folder also provided with a label, such as "private" or "business".
  • To delete the e-mails it is not enough simply to press only the appropriate button. To delete Thunderbird mails properly and completely, you have to additionally compress the folder. To do this, simply select instead of "New Folder ..." to select "Compress" from.Thunderbird slowly Overcrowded Inbox

2. Plug-in works or stops responding

PROBLEMWith plug-ins can be - similar to browser - extend the functionality of the program, such as playing music or videos. Is a plug-in "hang", the performance is not directly affected, making Thunderbird slowly. The same applies in the event that a plug-in crashes.

SOLUTION: To avoid performance limitations, should then be restarted after a crash Thunderbird closed. to hang the plug-in again, it must be uninstalled if necessary updated, or in the worst case again.


  • To test whether a plug-in Thunderbird makes slow, you can select the menu "Help" and then "reboot with Add-ons Disabled ...".Thunderbird start slowly again with Add-ons Disabled

  • The name of the crashed plugins is at the crash report that appears after every crash.Thunderbird crashed slowly add-on

  • To update plug-ins to choose from the top menu "Tools", then the option "Add-ons". In the add-on manager you then click on the gear icon at the top right and can then "Check for Updates".
    Update Thunderbird slowly add-on

3. Defective Gloda

PROBLEM: Use the global database, named Gloda, the search function is enabled within the mail program. If the database is corrupted, inconsistent or fragmented, and the search speed is limited.

SOLUTION: In order to build the global database new Thunderbird is first closed. Then you delete the file "global-messages-db.sqlite" Thunderbird profile. The Gloda is then automatically re-created again when you restart Thunderbird.


  • To access the Thunderbird profile, click on the Windows Start pad on the bottom right and are following character code in the command line:% APPDATA% \ Thunderbird \ Profiles \Thunderbird slowly Thunderbird profile

  • The deleted file "global-messages-db.sqlite" will be created automatically after the program start. Depending on how many messages are in the mailbox, the reconstruction may take some time to complete.Thunderbird slow global-messages-db.sqlite