diff --git a/locales/en.json b/locales/en.json
index 6e4fda2ac..0f8b3b861 100644
--- a/locales/en.json
+++ b/locales/en.json
@@ -455,7 +455,7 @@
     "system_upgraded": "The system has been upgraded",
     "system_username_exists": "Username already exists in the system users",
     "unbackup_app": "App '{app:s}' will not be saved",
-    "unexpected_error": "An unexpected error occured",
+    "unexpected_error": "An unexpected error occured: {error}",
     "unit_unknown": "Unknown unit '{unit:s}'",
     "unlimit": "No quota",
     "unrestore_app": "App '{app:s}' will not be restored",
diff --git a/src/yunohost/app.py b/src/yunohost/app.py
index 11f92afd1..9d1d8b447 100644
--- a/src/yunohost/app.py
+++ b/src/yunohost/app.py
@@ -830,11 +830,12 @@ def app_install(operation_logger, auth, app, label=None, args=None, no_remove_on
         )
     except (KeyboardInterrupt, EOFError):
         install_retcode = -1
-    except:
-        logger.exception(m18n.n('unexpected_error'))
+    except Exception:
+        import traceback
+        logger.exception(m18n.n('unexpected_error', traceback=u"\n" + traceback.format_exc()))
     finally:
         if install_retcode != 0:
-            error_msg = operation_logger.error(m18n.n('unexpected_error'))
+            error_msg = operation_logger.error(m18n.n('unexpected_error', traceback='shell command return code: %s' % install_retcode))
             if not no_remove_on_failure:
                 # Setup environment for remove script
                 env_dict_remove = {}