diff --git a/Casks/thunderbird-de.rb b/Casks/thunderbird-de.rb
deleted file mode 100644
index fafb718b7..000000000
--- a/Casks/thunderbird-de.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-de' do
-  version '45.4.0'
-  sha256 '31fea94bc6861dbb6e989fb1899d29d54b5a1ae6da50665ae0b922270b730291'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=de"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/de/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-fr.rb b/Casks/thunderbird-fr.rb
deleted file mode 100644
index 1f7c79688..000000000
--- a/Casks/thunderbird-fr.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-fr' do
-  version '45.4.0'
-  sha256 '6f6318bb2bb11071e06e83ff52f3fb5b96e2e72b461667fdf173c1c8121d09b5'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=fr"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/fr/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-gl.rb b/Casks/thunderbird-gl.rb
deleted file mode 100644
index ddfed2487..000000000
--- a/Casks/thunderbird-gl.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-gl' do
-  version '45.4.0'
-  sha256 '4f03e389ce1972db0b9225fd1272b52667ed09636fb83e53c096c774fecdd8e4'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=gl"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/gl/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-it.rb b/Casks/thunderbird-it.rb
deleted file mode 100644
index c9cd0562d..000000000
--- a/Casks/thunderbird-it.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-it' do
-  version '45.4.0'
-  sha256 '56168ea04a98e309e40fa98d72dce19a2f96898c21452fe904f893d22c6c56fc'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=it"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/it/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-ja.rb b/Casks/thunderbird-ja.rb
deleted file mode 100644
index 8dc664457..000000000
--- a/Casks/thunderbird-ja.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-cask 'thunderbird-ja' do
-  version '45.4.0'
-  sha256 'b5b73d0aa26dea74c7473875e8e112fe5ac4bb57a6d5042376475470154ae076'
-
-  # mozilla.org was verified as official when first introduced to the cask
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=ja-JP-mac"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.jp/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-nl.rb b/Casks/thunderbird-nl.rb
deleted file mode 100644
index ef4156c56..000000000
--- a/Casks/thunderbird-nl.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-nl' do
-  version '45.4.0'
-  sha256 '6c1402dd7bdddfe6dfecd96dc48eface9f388bb1798f6a8842602b55bf57450a'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=nl"
-  name 'Mozilla Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/nl/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-pt-br.rb b/Casks/thunderbird-pt-br.rb
deleted file mode 100644
index e77df72eb..000000000
--- a/Casks/thunderbird-pt-br.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-pt-br' do
-  version '45.4.0'
-  sha256 '314ec5dd4962acb9d0545fe2817a043aaae36cb1b576ec5083c9ef42cf22b53f'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=pt-BR"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/pt-BR/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-ru.rb b/Casks/thunderbird-ru.rb
deleted file mode 100644
index db58ee340..000000000
--- a/Casks/thunderbird-ru.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-ru' do
-  version '45.4.0'
-  sha256 '8b108549253327f4dd64102c182377bfce9b521ecbade02e4cc3cfcf30654f50'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=ru"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/ru/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-uk.rb b/Casks/thunderbird-uk.rb
deleted file mode 100644
index 8730be951..000000000
--- a/Casks/thunderbird-uk.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-uk' do
-  version '45.4.0'
-  sha256 '7cc800300dee7298cc2b2b1636f4a5213c15b24add42d928a7306a0d5478e1e6'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=uk"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/uk/thunderbird/'
-
-  app 'Thunderbird.app'
-end
diff --git a/Casks/thunderbird-zh-cn.rb b/Casks/thunderbird-zh-cn.rb
deleted file mode 100644
index dd5959dba..000000000
--- a/Casks/thunderbird-zh-cn.rb
+++ /dev/null
@@ -1,10 +0,0 @@
-cask 'thunderbird-zh-cn' do
-  version '45.4.0'
-  sha256 '2114bc9098a054e0d6ac70173e711eb66e755a37c1f55bc9769efe1800791b3b'
-
-  url "https://download.mozilla.org/?product=thunderbird-#{version}&os=osx&lang=zh-CN"
-  name 'Mozilla Thunderbird'
-  homepage 'https://www.mozilla.org/zh-CN/thunderbird/'
-
-  app 'Thunderbird.app'
-end