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Updated to 45.4.0 and now add-ons won't install

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This is happening on Windows 8.1.

If I open Thunderbird with my existing profile, Lightning is disabled because it's deemed incompatible.

If I create a new profile, no add-ins install at all. They appear to install and I get the link to restart Thunderbird, but when I do, no add-ons are present. This also happens with a fresh install of Thunderbird.

This is happening on Windows 8.1. If I open Thunderbird with my existing profile, Lightning is disabled because it's deemed incompatible. If I create a new profile, no add-ins install at all. They appear to install and I get the link to restart Thunderbird, but when I do, no add-ons are present. This also happens with a fresh install of Thunderbird.

All Replies (6)

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Well that is three issues.

But have you tried simply removing lightning and restarting Thunderbird and re adding it?

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Absolutely, I have tried that, and with no success.

I have also tried that on Windows 7.

A fresh install on Windows 7 doesn't allow Add-ins to be installed either.

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have you tried disabling your anti virus then? It sounds to me like something is preventing normal operating. Either UAC or anti virus are the two likely culprits. But as UAC usually has messages I am guessing the other.

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Yes. I disabled anti-virus software. On two versions of the Windows OS, each with different anti-virus programs. I was still unsuccessful.

45.3.0 for Linux works well. So on a lark, I reverted to 45.3.0 for Windows and it still failed.

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Try another lark... run Thunderbird as administrator.

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The behavior is the same. I can't install extensions even when running Thunderbird as administrator.