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Thunderbird Not Responding Constantly - Windows 10

  • 5 replies
  • 1 has this problem
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  • Last reply by Wayne Mery

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I've been using the same Thunderbird profile for easily a decade. It worked fine on all of my previous machines. But since I moved to Windows 10, it's been horribly slow and constantly hangs on "not responding." As of yesterday, it's now so non-responsive I can't even manage to see my inbox at all. Things I've tried:

- Opening Thunderbird in Safe Mode with all extensions disabled
- Running Thunderbird in Compatibility Mode
- Running CC Cleaner
- Installing a different version of Thunderbird
- Running Thunderfix (this seemed to make things worse)
- Making sure that Windows Defender has Thunderbird listed (it does)

I don't have any other anti-virus programs running.

Help? At this point Thunderbird is completely unusable.

I've been using the same Thunderbird profile for easily a decade. It worked fine on all of my previous machines. But since I moved to Windows 10, it's been horribly slow and constantly hangs on "not responding." As of yesterday, it's now so non-responsive I can't even manage to see my inbox at all. Things I've tried: - Opening Thunderbird in Safe Mode with all extensions disabled - Running Thunderbird in Compatibility Mode - Running CC Cleaner - Installing a different version of Thunderbird - Running Thunderfix (this seemed to make things worse) - Making sure that Windows Defender has Thunderbird listed (it does) I don't have any other anti-virus programs running. Help? At this point Thunderbird is completely unusable.

All Replies (5)

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I still have issues with my upgraded windows 10. but the micro freezes I am seeing are windows wide, not just Thunderbird. Took a long time to realize that as Firefox and Thunderbird are my primarily used software.

Some thing I have done which "helped"

Disabled windows defraging the disks all the time. (remember when they said we no longer needed to do it at all) Disable windows search indexing the Thunderbird profile folder. I have no idea what the index is used for, no file manager still appears to work. plus some other windows suggestions I found on the web. Now if I could just make it remeber the DNS information instead of reporting site I am on as "unknown". But I digress.

\In Thunderbird I disabled the allow windows search to index mail and manually deleted he 100,000 plus mozeml files in my profile and all the mozmsg folders. All unnecessary.

I deleted the global-index-db.sqlite file. I got no real result from it, but faster searches.

Where ccleaner is concerned, make sure it is configured to not make any changes to Thunderbird. It has a habit of deleting system setting files to protect your privacy. Been doing it for years.

Thunderbird fix deletes all the MSF files in the profile. First ime you start Thunderbird after they all have to be recreated. make a slowness issue worse until they are all regenerated.

Other things to look at is an exclusion for the anti virus from scanning the files in the Thunderbird profile. Nothing slows things more than a stupid scan when you are trying to update a 4Gb data file.

Disabling email scanning is also probably a good idea. just make sure to enable the anti virus option in Thunderbird settings. That makes a file containing all new mail available to the anti virus to scan before Thunderbird does anything with it.

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A quick test (to short cut) is start *Windows'* safe mode with networking enabled - win10 https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird

Does problem go away?

Please reply to let us know results.

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I tried to start Windows in Safe Mode with Networking. It starts me in safe mode, but my computer can ONLY connect with wifi, and Windows 10 safe mode with networking apparently doesn't load wifi drivers. Went through a whole rabbit whole on this as well, and apparently "with networking" requires functioning with an Ethernet cable - and my computer is new enough that it doesn't even have a port that supports this.

So no luck on that - Thunderbird started, but I can't tell if it had issues or not because it couldn't connect to the internet.

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Things I tried doing also, per the other response above:

- Disabled Windows defragging - Disable windows search indexing the Thunderbird profile folder - In Thunderbird disabled the allow windows search to index mail - There were no mozeml or mozmsg files/folders - Deleted the global-index-db.sqlite

Any other ideas? Thunderbird is still Not Responding so much as to be unusable.

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> Any other ideas? Thunderbird is still Not Responding so much as to be unusable.

Did you do the full list at https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems ??