Upgrade to moodle v 3.1.7 fails during language check

 I tried to update my moodle 3.1.12 Installation to 3.1.17

the language pack is :de

with other language packs the update works. So maybe the language pack is defect?

this are the errors:

Fuehre Aktualisierung aus...
-->Sprachpakete verwalten: de
Default exception handler: Die Überprüfung der heruntergeladenen Datei ist gescheitert Debug: de
Error code: downloadedfilecheckfailed

• line 807 of /lib/componentlib.class.php: lang_installer_exception thrown
• line 662 of /lib/componentlib.class.php: call to lang_installer->install_language_pack()
• line 45 of /admin/tool/langimport/lib.php: call to lang_installer->run()
• line 1582 of /lib/upgradelib.php: call to tool_langimport_preupgrade_update()
• line 1669 of /lib/upgradelib.php: call to upgrade_language_pack()
• line 175 of /admin/cli/upgrade.php: call to upgrade_core()

!!! Die Überprüfung der heruntergeladenen Datei ist gescheitert !!!
!! de
Error code: downloadedfilecheckfailed !!
!! Stack trace: * line 807 of /lib/componentlib.class.php: lang_installer_exception thrown

• line 662 of /lib/componentlib.class.php: call to lang_installer->install_language_pack()
• line 45 of /admin/tool/langimport/lib.php: call to lang_installer->run()
• line 1582 of /lib/upgradelib.php: call to tool_langimport_preupgrade_update()
• line 1669 of /lib/upgradelib.php: call to upgrade_language_pack()
• line 175 of /admin/cli/upgrade.php: call to upgrade_core()
  !!
  konnte Aktualisierung nicht furchfuehren Fehler 256