▼テンプレート
[EC-CUBE] 4.0.3
[OS] Ubuntu 18.04.5 LTS (GNU/Linux 5.4.0-1030-aws x86_64)
[PHP] PHP Version => 7.2.24-0ubuntu0.18.04.7
[データベース] Server version: 5.7.32-0ubuntu0.18.04.1-log (Ubuntu)
[WEBサーバ] Server version: Apache/2.4.29 (Ubuntu)
[現象] お世話になります。管理画面->テンプレート一覧からDLしたテンプレートファイルをローカルPCで解凍しようと思うとすると
tar: Error opening archive: Unrecognized archive format
となり解凍できません。
mac の環境でも windows の環境でも同僚PCでも同じなのでファイルが壊れているのではないかと思います。
サーバ側のログで apache , php , ec-cube のログには特にエラーやワーニングが出てないようで
php も再インストールしてみましたが変化がありません。
あとどこを調べてみればよいのか、または何を試してよいのかどなたかご教示願えないでしょうか？
何卒よろしくお願いします。

####################################################################################################
####################################### 20/Dec/2020 16:28:37 #####################################
####################################################################################################
___ ADMIN __________________________________________________________________________________________
INIT
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/src/Eccube/Log/Logger.php, line: 64, class: Eccube\Log\Logger, function: log, uid: 4351e3c, user_id: N/A, session_id: N/A }
___ REQUEST ________________________________________________________________________________________
Matched route "admin_store_template_download".
--> route: admin_store_template_download
--> route_parameters:
_controller: 'Eccube\Controller\Admin\Store\TemplateController::download'
id: '11'
_route: admin_store_template_download
--> request_uri: 'https://hogehoge.co.jp/testadmin/store/template/11/download'
--> method: GET
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/vendor/symfony/http-kernel/EventListener/RouterListener.php, line: 125, class: Symfony\Component\HttpKernel\EventListener\RouterListener, function: onKernelRequest, uid: 4351e3c, user_id: N/A, session_id: N/A }
___ (!) SECURITY ___________________________________________________________________________________
Read existing security token from the session.
--> key: _security_admin
--> token_class: Symfony\Component\Security\Core\Authentication\Token\UsernamePasswordToken
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/vendor/symfony/security/Http/Firewall/ContextListener.php, line: 99, class: Symfony\Component\Security\Http\Firewall\ContextListener, function: handle, uid: 4351e3c, user_id: N/A, session_id: k89ls8dma1qkhsu76vu3ejkmt5 }
___ (!) SECURITY ___________________________________________________________________________________
User was reloaded from a user provider.
--> provider: Eccube\Security\Core\User\MemberProvider
--> username: test@hogehoge.co.jp
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/vendor/symfony/security/Http/Firewall/ContextListener.php, line: 203, class: Symfony\Component\Security\Http\Firewall\ContextListener, function: refreshUser, uid: 4351e3c, user_id: N/A, session_id: k89ls8dma1qkhsu76vu3ejkmt5 }
___ ADMIN __________________________________________________________________________________________
PROCESS START
--> - admin_store_template_download
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/src/Eccube/Log/Logger.php, line: 64, class: Eccube\Log\Logger, function: log, uid: 4351e3c, user_id: 1, session_id: k89ls8dma1qkhsu76vu3ejkmt5 }
___ ADMIN __________________________________________________________________________________________
Begin Transaction.
___ ADMIN __________________________________________________________________________________________
LOGIC START
--> - admin_store_template_download
___ ADMIN __________________________________________________________________________________________
LOGIC END
--> - admin_store_template_download
___ (!) SECURITY ___________________________________________________________________________________
Stored the security token in the session.
--> key: _security_admin
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/vendor/symfony/security/Http/Firewall/ContextListener.php, line: 144, class: Symfony\Component\Security\Http\Firewall\ContextListener, function: onKernelResponse, uid: 4351e3c, user_id: 1, session_id: k89ls8dma1qkhsu76vu3ejkmt5 }
___ APP ____________________________________________________________________________________________
PROCESS END
--> - admin_store_template_download
--> extra: { url: /testadmin/store/template/11/download, ip: 180.50.56.204, http_method: GET, server: hogehoge.co.jp, referrer: 'https://hogehoge.co.jp/testadmin/store/template', user_agent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36', file: /var/www/hogehoge.co.jp/src/Eccube/Log/Logger.php, line: 68, class: Eccube\Log\Logger, function: log, uid: 4351e3c, user_id: 1, session_id: N/A }
___ APP ____________________________________________________________________________________________
Commit executed.
___ APP ____________________________________________________________________________________________
remove temp file: /tmp/a6d94909262a7a755908b5310b103d826b9bbdbd
___ APP ____________________________________________________________________________________________
remove temp file: /tmp/a6d94909262a7a755908b5310b103d826b9bbdbd.tar
___ APP ____________________________________________________________________________________________
remove temp file: /tmp/a6d94909262a7a755908b5310b103d826b9bbdbd.tar.gz

今更ですが自己解決しました。
テンプレートソースに変な制御コードが含まれていたため tar ファイルを解凍しようとするときにエラーになっていました。