"Not Responding" in Windows with long operations scanning messages or reading messages (not caused by accessibility)
When scanning headers and/or reading messages there are long delays with OS pop up saying Thunderbird is unresponsive. It typically happens when downloads and copying are occurring in the background. TB seems to be giving too much priority to the background making everything in the foreground slow and frequently stop completely. When composing a message a typed line does not appear for 20 seconds or more making it difficult to prevent typing errors. I have not had this problem with older versions of TB. My local message store is well over 20 GB. I expect some operations to take awhile but none should slow or stop response to immediate entry. When TB logs into servers and there are network problems input at the keyboard is often ignored completely. To regain control I have to call the task manager and do end process and restart TB. At first I thought this was a problem with one computer. I have several with a mix of several versions of Windows (7,8,10 and 11) with several email addresses and have the same problem in varying degrees with all of them. If this is a setting problem I have no clue how to fix. I have been using TB more than a decade and feel confident about how to do most operations. I'm using version 140.3.0esr (64bit).
Modified by Wayne Mery
All Replies (5)
Try this, which should at least help with the composing issue:
- go to TB menu > Settings > General
- scroll all the way down and click the 'Config editor' button on the right
- click 'Accept the risk and continue' if that appears
- search for accessibility.force_disabled > change the value to 1 > click the check mark
- restart TB
It had little or no effect. I had suspicions about an overheated processor on one PC until I tried a different PC with TB and got a similar behavior. My mail store occupies more than 15 GB in both PCs.
Try these one at a time, testing after each.
---
Add exclusions in Windows Defender for the TB executable and the TB Profiles folder:
- in Windows, click Start and type: virus
- click Virus & threat protection System settings > Virus & threat protection settings > Manage settings
- scroll down to Exclusions > click 'Add an exclusion' > File
- navigate to and select the Thunderbird.exe file (usually in C:\Program Files\Mozilla Thunderbird folder) > click 'Open'
- to locate the executable:
- TB menu > Help > Troubleshooting Information
- Application Basics section > 'Application Binary'
- click 'Add an exclusion' > Folder
- navigate to and select the Thunderbird Profiles folder (all profiles - usually at C:\Users\<username>\AppData\Roaming\Thunderbird\Profiles) > click 'Select Folder'
- to locate the Profiles folder:
- TB menu > Help > Troubleshooting Information
- Application Basics section > scroll down to 'Profile folder > click the 'Open Folder' button
- navigate up two levels
\***Important\***: go to TB menu > Settings > Privacy & Security > Security > Antivirus and enable 'Allow antivirus clients to quarantine individual incoming messages'.
---
Clear the cache:
- press Ctrl-Shift-Delete (Mac: Cmd-Shift-Delete)
- set 'Time range...' to 'Everything'
- untick all items except 'Cache'
- clear > restart TB
---
Compact folders (this may take quite a while):
- TB menu bar > File > Compact Folders
(If you don't see the menu bar on top, press the ALT key.)
---
See [Thunderbird:Testing:Antivirus_Related_Performance_Issues](https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues)
See [Thunderbird:Testing:Memory Usage Problems](https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems)
Run a [Performance profile](https://support.mozilla.org/en-US/kb/profiling-thunderbird-performance)
You must log in to your account to reply to posts. Please start a new question, if you do not have an account yet.