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TB 78.6.0 on Win 10: All extensions / add-ons deactivated; any add-on install impossible with "corrupted"

user33838888605474793213753787801073609399
user33838888605474793213753787801073609399

Hi, sometime in the last 7 days thunderbird stopped working with extensions. They all are now deactivated with no option to activate them again. And this is not due to incompatibility with TB 78. They worked on TB 78. I downgraded to earlier 78.1 and no change.

I also can not install any other new add-on as a pop-up comes up that says the add-on file couldnt be installed because it was corrupted. This happens with both the TB internal install option as well as install via file.

I have no custom themes installed.

Running on Win 10 20H2, 64bit.

Any tips on what I should do?

Hi, sometime in the last 7 days thunderbird stopped working with extensions. They all are now '''deactivated '''with no option to activate them again. And this is not due to incompatibility with TB 78. They worked on TB 78. I downgraded to earlier 78.1 and no change. I also can not install any other new add-on as a pop-up comes up that says the add-on file couldnt be installed because it was '''corrupted'''. This happens with both the TB internal install option as well as install via file. I have no custom themes installed. Running on Win 10 20H2, 64bit. Any tips on what I should do?

Chosen solution

The xpi file may be getting corrupted due to AV software. Suggest test: Exit Thunderbird. Restart computer in 'Safe Mode with Networking'. Then start up Thunderbird. attempt uninstall or enable addons attempt download of addon.

report back on results.

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All Replies (3)

Toad-Hall
Toad-Hall
  • Top 10 Contributor

Chosen Solution

The xpi file may be getting corrupted due to AV software. Suggest test: Exit Thunderbird. Restart computer in 'Safe Mode with Networking'. Then start up Thunderbird. attempt uninstall or enable addons attempt download of addon.

report back on results.

Toad-Hall
Toad-Hall
  • Top 10 Contributor

Also try this: In Thunderbird

  • Menu app icon > Options > General
  • scroll to the bottom
  • click on 'Config Editor' button
  • Accept warning
  • In search type: install
  • Look for this line: xpinstall.signatures.required

If set to 'True':

  • Double click on that line to toggle value to 'False'
  • close 'about:config' - top right X

Restart Thunderbird.

Check to see if addons get auto enabled or whether you can enable them.

user33838888605474793213753787801073609399
user33838888605474793213753787801073609399 Question owner

Toad-Hall said
Also try this: In Thunderbird
  • Look for this line: xpinstall.signatures.required

Thanks I tried this as well, but the signatures setting already was on FALSE.