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Why is thunderbird so slow and keeps not responding?

  • 12 cavab
  • 25 have this problem
  • 4 views
  • Last reply by Matt

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Takes ages to go through emails as thunderbird is continually not responding and is slow. opening and or deleting creates the same problem with message that thunderbird is not responding.

Takes ages to go through emails as thunderbird is continually not responding and is slow. opening and or deleting creates the same problem with message that thunderbird is not responding.

All Replies (12)

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Is it Thunderbird or windows 10.

I have battled for some time what I thought was Thunderbird and Firefox freezing. Only to learn it is windows 10 that is taking these sabbaticals at the most annoying times and loosing what I type.

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This does not answer my question. How do I solve the problem? If it is windows 10 how can I find out this and how to solve it?

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Could be a bunch of things:

Try "Tools -> Activity Manager" to see what Thunderbird is spending it's time doing ("Activity Manager" is the wrong name. It's really an activity *monitor*)

Do you have any filters that automatically scan mail when it's read? (Tools -> Message filters). Be especially careful of filters that scan the email body

Are you using IMAP or POP email access? Tools -> Account Settings -> then "server settings" under the email row in the left column. Then look for "server type" in the top right.

Do you have large folders? If so, try a right clicking on that folder and running the "compact" option for that folder (especially inbox folders). Note, this can take an hour or two to finish for large folders.

One last thing, Thunderbird migrated one of it's core email structure encoding functions from C code to Javascript. That makes searching slower which means Thunderbird is busier and the user interface is less responsive when doing background activity involving searches . (bugzilla.mozilla.org bugs 1055077 and 1284753). Did the slowness start sometime after 2014?

Modified by Ben Slade

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None of above helped. why is it so complicated to solve this problem. I will have to consider not using Mozilla Thunderbird as it is very frustrating.

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If it is windows 10 how can I find out this and how to solve it?

http://thunderbirdtweaks.blogspot.de/2016/08/windows-10-and-thunderbird-firefox.html

Another candidate for causing problems typically is anti-virus software.

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A good starting point / standard diagnostic:

Start *Windows'* safe mode with networking enabled - win10 https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode - win8 https://support.microsoft.com/en-us/help/17076/windows-8-startup-settings-safe-mode - win7 https://support.microsoft.com/en-us/help/17419/windows-7-advanced-startup-options-safe-mode#start-computer-safe-mode=windows-7 - XP https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx

Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird

Does problem go away?

If yes, then try thunderbird in normal mode with Windows still in safe mode.

Please reply to let us know results.

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^^^^

This goes for all 15 people who think they have this problem

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Hmm, now 19 people think they have this problem.

But no one posts. Odd

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Wayne Mery said

Hmm, now 19 people think they have this problem. But no one posts. Odd

By "no one posts", do you mean no developers have posted an answer? Or that no other users are complaining about it?

Note that, in my 10/11/2016 comment I pointed out that this could be a basic architecture decision by the developers to implement some core code that is easier to write and maintain, but significantly slower. Given the very limited number of people maintaining Thunderbird, this may never be fixed.

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BenjaminGSlade said

Wayne Mery said
Hmm, now 19 people think they have this problem. But no one posts. Odd

By "no one posts", do you mean no developers have posted an answer? Or that no other users are complaining about it?

There is no reason for developers to post here - because there is no single answer. My "no one posts" refers to users who seems to me have missed my questions at https://support.mozilla.org/en-US/questions/1142517#answer-937674 ... or perhaps found that those items helped.

BenjaminGSlade said

Note that, in my 10/11/2016 comment I pointed out that this could be a basic architecture decision by the developers to implement some core code that is easier to write and maintain, but significantly slower. Given the very limited number of people maintaining Thunderbird, this may never be fixed.

I would not expect "go through emails" stated in the initial post to be related to jsmime changes.

In other words, the jsmime changes you refer to impacts only very specific cases, like JSMime header parsing makes quick filter slow , but not overall Thunderbird performance. Again, see my earlier posting

Modified by Wayne Mery

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Re: users who seems to me have missed my questions at https://support.mozilla.org/en-US/questions/1142517#answer-937674 ...

Oh I see. Thanks for trying to help them, by the way.

Re: the jsmime changes you refer to impacts only very specific cases

I hope that's true. JSMime could get called anytime an email get's parsed for various reasons. Given that an interpreted Javascript subroutine could run hundreds or thousands of times slower than a tight C subroutine, and it could be called for each email in folder, is it really an edge case?

For example, I wonder if the global indexing that occurs in the background uses a lot more CPU (aka "Gloda". Details at: https://developer.mozilla.org/en-US/docs/Mozilla/Thunderbird/gloda ). Maybe only noticable in unusual situations. Like when you have an IMAP problem and need to resync a huge mail folder.

Also, if you have filters running they could use a lot more CPU.

There's no user tool in Thunderbird to show where it's spending it's time by CPU time and elapsed clock time. So it would be hard for normal users to see these problems.

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Wayne Mery said

Hmm, now 19 people think they have this problem. But no one posts. Odd

That is the fundamental issue with offering such a button. Folk click on it because they think it does something, in this case subscribes them to the non existent discussion about their specific problem that may or may not be related to that of the other 18 that clicked the button.

We know.

  • Anti virus is an issue, depending on the product and it's version. Clicking Me to does not cover that sort of thing at all.
  • Windows 10 networking can be a mess that makes things move like molasses. Some of the network drivers are sub optimal, but they are improving.
  • Windows power saving features are buggy at best.
  • Me to for Thunderbird freezing does not address the 700,000 google hits one gets for "why does windows 10 keep freezing"
  • Some folk only see an issue in Thunderbird because it and Firefox are the only things they use most days (me for instance) so their complaint really should be the point above, but they do not know that yet.

Basically I ignore the number of "me to" people saying they have the problem as they may or may not have it. Full diagnosis is required for something like this, not a one button click that subscribes you the the discussion email.