diff --git a/freqtrade/optimize/hyperopt.py b/freqtrade/optimize/hyperopt.py
index b8745a644..b22aa58c5 100644
--- a/freqtrade/optimize/hyperopt.py
+++ b/freqtrade/optimize/hyperopt.py
@@ -12,7 +12,6 @@ from math import ceil
 from pathlib import Path
 from typing import Any, Dict, List, Optional
 
-import numpy as np
 import progressbar
 import rapidjson
 from colorama import Fore, Style
diff --git a/freqtrade/strategy/hyper.py b/freqtrade/strategy/hyper.py
index 881d592d9..a31a3b39f 100644
--- a/freqtrade/strategy/hyper.py
+++ b/freqtrade/strategy/hyper.py
@@ -327,10 +327,10 @@ class HyperStrategyMixin(object):
             try:
                 params = json_load(filename.open('r'))
                 if params.get('strategy_name') != self.__class__.__name__:
-                    raise OperationalException('Invalid parameter file provided')
+                    raise OperationalException('Invalid parameter file provided.')
                 return params
             except ValueError:
-                logger.warning("Invalid parameter file.")
+                logger.warning("Invalid parameter file format.")
                 return {}
         logger.info("Found no parameter file.")
 
diff --git a/tests/optimize/test_hyperopt.py b/tests/optimize/test_hyperopt.py
index 91d9f5496..f0a2342c5 100644
--- a/tests/optimize/test_hyperopt.py
+++ b/tests/optimize/test_hyperopt.py
@@ -1020,5 +1020,3 @@ def test_SKDecimal():
     assert space.transform([2.0]) == [200]
     assert space.transform([1.0]) == [100]
     assert space.transform([1.5, 1.6]) == [150, 160]
-
-
diff --git a/tests/strategy/test_interface.py b/tests/strategy/test_interface.py
index 04d12a51f..714e28929 100644
--- a/tests/strategy/test_interface.py
+++ b/tests/strategy/test_interface.py
@@ -1,6 +1,7 @@
 # pragma pylint: disable=missing-docstring, C0103
 import logging
 from datetime import datetime, timedelta, timezone
+from pathlib import Path
 from unittest.mock import MagicMock
 
 import arrow
@@ -692,3 +693,50 @@ def test_auto_hyperopt_interface(default_conf):
 
     with pytest.raises(OperationalException, match=r"Inconclusive parameter.*"):
         [x for x in strategy.detect_parameters('sell')]
+
+
+def test_auto_hyperopt_interface_loadparams(default_conf, mocker, caplog):
+    default_conf.update({'strategy': 'HyperoptableStrategy'})
+    del default_conf['stoploss']
+    del default_conf['minimal_roi']
+    mocker.patch.object(Path, 'is_file', MagicMock(return_value=True))
+    mocker.patch.object(Path, 'open')
+    expected_result = {
+        "strategy_name": "HyperoptableStrategy",
+        "params": {
+            "stoploss": {
+                "stoploss": -0.05,
+            },
+            "roi": {
+                "0": 0.2,
+                "1200": 0.01
+            }
+        }
+    }
+    mocker.patch('freqtrade.strategy.hyper.json_load', return_value=expected_result)
+    PairLocks.timeframe = default_conf['timeframe']
+    strategy = StrategyResolver.load_strategy(default_conf)
+    assert strategy.stoploss == -0.05
+    assert strategy.minimal_roi == {0: 0.2, 1200: 0.01}
+
+    expected_result = {
+        "strategy_name": "HyperoptableStrategy_No",
+        "params": {
+            "stoploss": {
+                "stoploss": -0.05,
+            },
+            "roi": {
+                "0": 0.2,
+                "1200": 0.01
+            }
+        }
+    }
+
+    mocker.patch('freqtrade.strategy.hyper.json_load', return_value=expected_result)
+    with pytest.raises(OperationalException, match="Invalid parameter file provided."):
+        StrategyResolver.load_strategy(default_conf)
+
+    mocker.patch('freqtrade.strategy.hyper.json_load', MagicMock(side_effect=ValueError()))
+
+    StrategyResolver.load_strategy(default_conf)
+    assert log_has("Invalid parameter file format.", caplog)