diff --git a/HISTORY.rst b/HISTORY.rst
index 29b2bb9c..1e6de9c1 100644
--- a/HISTORY.rst
+++ b/HISTORY.rst
@@ -7,6 +7,9 @@ PlatformIO 2.0
 2.8.7 (2016-??-??)
 ~~~~~~~~~~~~~~~~~~
 
+* Don't check OS type for ARM mbed-enabled boards and ST STM32 development
+  platform before uploading to disk
+  (`issue #596 <https://github.com/platformio/platformio/issues/596>`_)
 * Fixed broken compilation for Atmel SAMD based boards except Arduino Due
   (`issue #598 <https://github.com/platformio/platformio/issues/598>`_)
 
diff --git a/platformio/builder/scripts/ststm32.py b/platformio/builder/scripts/ststm32.py
index ac1bc604..42047105 100644
--- a/platformio/builder/scripts/ststm32.py
+++ b/platformio/builder/scripts/ststm32.py
@@ -100,10 +100,7 @@ AlwaysBuild(target_size)
 # Target: Upload by default .bin file
 #
 
-disable_msd = (
-    (platform.system() == "Darwin" and platform.release().startswith("14.")) or
-    env.subst("$UPLOAD_PROTOCOL"))
-if "mbed" in env.subst("$FRAMEWORK") and not disable_msd:
+if "mbed" in env.subst("$FRAMEWORK") and not env.subst("$UPLOAD_PROTOCOL"):
     upload = env.Alias(["upload", "uploadlazy"],
                        target_firm, env.UploadToDisk)
 else: