diff --git a/install/opm b/install/opm
index e6e62bc7b..f5b622440 100644
--- a/install/opm
+++ b/install/opm
@@ -5,4 +5,4 @@ THISDIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
 LIB="$THISDIR/../lib"
 OPM=$LIB/opm/src/cmd/opm.os
 
-oscript $OPM "$@"
+"$THISDIR/oscript" "$OPM" "$@"
diff --git a/install/opm.bat b/install/opm.bat
index 1105eba2c..d968ccde3 100644
--- a/install/opm.bat
+++ b/install/opm.bat
@@ -2,7 +2,7 @@
 
 setlocal
 
-set lib="%~dp0..\lib"
+set lib=%~dp0..\lib
 set opm=%lib%\opm\src\cmd\opm.os
 
-oscript %opm% %*
+"%~dp0oscript.exe" "%opm%" %*