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Èròjà atẹ̀lélànà yii ni a ti fi pamọ́ fọ́jọ́ pípẹ́. Jọ̀wọ́ béèrè ìbéèrè titun bí o bá nílò ìrànwọ́.

"The addon could not be downloaded because of a connection failure"

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gordongeise
gordongeise
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New Dell Precision 3800 running Windows 7. Installed latest Firefox from the Mozilla site. For the first time ever in my experience, Firefox is refusing various sites from asking to install add-ons. I click "Allow" and another alert shows up with the subject advice.

I've been through the help. The closest article advised me to add the site(s) trying to install add-ons to my "Exceptions" list under Options > Security > Warn me when sites try to install add-ons. But I don't even have that box checked, so "Exceptions" is grayed out.

I've Googled. Somebody a couple years ago suggested (and several others said "yay that worked") adding a string in about:config called xpinstall.enabled and making it "True". String sounded wrong so I tried Boolean. Didn't work. I tried string anyway. Didn't work. Nothing works except downloading the add-on install files and opening them with Firefox. That sucks. Now it's not even showing me an "Allow" button to click. Very. Very. Very. Very. Very. Frustrating. Very. Did I mention Very?

New Dell Precision 3800 running Windows 7. Installed latest Firefox from the Mozilla site. For the first time ever in my experience, Firefox is refusing various sites from asking to install add-ons. I click "Allow" and another alert shows up with the subject advice. I've been through the help. The closest article advised me to add the site(s) trying to install add-ons to my "Exceptions" list under Options > Security > Warn me when sites try to install add-ons. But I don't even have that box checked, so "Exceptions" is grayed out. I've Googled. Somebody a couple years ago suggested (and several others said "yay that worked") adding a string in about:config called xpinstall.enabled and making it "True". String sounded wrong so I tried Boolean. Didn't work. I tried string anyway. Didn't work. Nothing works except downloading the add-on install files and opening them with Firefox. That sucks. Now it's not even showing me an "Allow" button to click. Very. Very. Very. Very. Very. Frustrating. Very. Did I mention Very?

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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It is more likely that either an extension or other (possibly security) software is blocking downloading extensions. There shouldn't be any problems with downloading and installing an extension if you click the allow button.

You can inspect and manage the permissions for the domain in the currently selected tab via these steps:

  • Click the "Site Identity Button" (globe/padlock) on the location/address bar
  • Click "More Information" to open "Tools > Page Info" with the Security tab selected
  • Go to the Permissions tab (Tools > Page Info > Permissions) to check the permissions for the domain in the currently selected tab

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.