diff --git a/moviepy/config.py b/moviepy/config.py
index 64035f4fa..5a8451607 100644
--- a/moviepy/config.py
+++ b/moviepy/config.py
@@ -65,8 +65,9 @@ def try_cmd(cmd):
     success, err = try_cmd([IMAGEMAGICK_BINARY])
     if not success:
         raise IOError(
-            str(err) +
-            " - The path specified for the ImageMagick binary might be wrong")
+            "%s - The path specified for the ImageMagick binary might be wrong: %s" %
+            (err, IMAGEMAGICK_BINARY)
+        )
 
 
 
diff --git a/tests/test_tools.py b/tests/test_tools.py
index b1510bb6c..0c5cd9eda 100644
--- a/tests/test_tools.py
+++ b/tests/test_tools.py
@@ -2,9 +2,9 @@
 """Tool tests meant to be run with pytest. Taken from PR #121 (grimley517)."""
 import sys
 import time
+import pytest
 
 import moviepy.tools as tools
-import pytest
 
 
 def test_ext():
@@ -69,17 +69,6 @@ def test_5():
     file = sys.stdout.read()
     assert file == b""
 
-def test_6():
-    """Test subprocess_call for operation.
-
-    The process sleep should run for a given time in seconds.
-    This checks that the process has deallocated from the stack on
-        completion of the called process.
-
-    """
-    process = tools.subprocess_call(["sleep" , '1'])
-    time.sleep(1)
-    assert process is None
 
 if __name__ == '__main__':
-   pytest.main()
+    pytest.main()