diff --git a/locales/en.json b/locales/en.json
index a182c7559..ba0d7e3cd 100644
--- a/locales/en.json
+++ b/locales/en.json
@@ -23,6 +23,7 @@
     "app_incompatible": "The app {app} is incompatible with your YunoHost version",
     "app_install_files_invalid": "These files cannot be installed",
     "app_install_failed": "Could not install {app}",
+    "app_install_script_failed": "An error occured inside the app installation script.",
     "app_location_already_used": "The app '{app}' is already installed in ({path})",
     "app_make_default_location_already_used": "Can't make the app '{app}' the default on the domain, {domain} is already in use by the other app '{other_app}'",
     "app_location_install_failed": "Cannot install the app there because it conflicts with the app '{other_app}' already installed in '{other_path}'",
diff --git a/src/yunohost/app.py b/src/yunohost/app.py
index af6c5d522..57df36713 100644
--- a/src/yunohost/app.py
+++ b/src/yunohost/app.py
@@ -917,7 +917,7 @@ def app_install(operation_logger, app, label=None, args=None, no_remove_on_failu
         # "Common" app install failure : the script failed and returned exit code != 0
         install_failed = (install_retcode != 0)
         if install_failed:
-            error = m18n.n('unexpected_error', error='shell command return code: %s' % install_retcode)
+            error = m18n.n('app_install_script_failed')
             logger.exception(error)
             operation_logger.error(error)
     # Script got manually interrupted ... N.B. : KeyboardInterrupt does not inherit from Exception