diff --git a/bootstrap/win/win_tools.bat b/bootstrap/win/win_tools.bat
index 55f85cef9..48b038d65 100644
--- a/bootstrap/win/win_tools.bat
+++ b/bootstrap/win/win_tools.bat
@@ -64,8 +64,12 @@ for /f "tokens=2,3 delims=. " %%i in ("%VERSTR%") do (set VERMAJOR=%%i & set VER
 if %VERMAJOR% lss 5 set GIT_VERSION=%GIT_VERSION%-xp
 if %VERMAJOR% equ 5 if %VERMINOR% lss 2 set XP_SUFFIX=-xp
 
+:: must explicitly use FIND_EXE to prevent this from grabbing e.g. gnuwin32 or
+:: msys versions.
+set FIND_EXE=%SYSTEMROOT%\System32\find.exe
+
 :: Check to see if we're on a 32 or 64 bit system
-reg Query "HKLM\Hardware\Description\System\CentralProcessor\0" | find /i "x86" > NUL && set OS_BITS=32 || set OS_BITS=64
+reg Query "HKLM\Hardware\Description\System\CentralProcessor\0" | %FIND_EXE% /i "x86" > NUL && set OS_BITS=32 || set OS_BITS=64
 
 if not exist "%WIN_TOOLS_ROOT_DIR%\.git_bleeding_edge" goto :GIT_OLD_FLOW
 set GIT_PORTABLE_FLOW=1
diff --git a/update_depot_tools b/update_depot_tools
index 64861c387..0177877d4 100755
--- a/update_depot_tools
+++ b/update_depot_tools
@@ -28,8 +28,8 @@ fi
 # Don't try to use Cygwin tools.  Get real win32 tools using the batch script.
 OUTPUT="$(uname | grep 'CYGWIN')"
 CYGWIN=$?
-if [ $CYGWIN = 0 ]; then
-  cmd /c `cygpath -w "$base_dir/bootstrap/win/win_tools.bat"`
+if [ $CYGWIN = 0 ] || [ $MINGW = 0 ]; then
+  $COMSPEC /c `cygpath -w "$base_dir/bootstrap/win/win_tools.bat"`
 fi
 
 CANONICAL_GIT_URL="https://chromium.googlesource.com/chromium/tools/depot_tools.git"