diff --git a/lib/tbb_2020.3/build/windows.inc b/lib/tbb_2020.3/build/windows.inc
index 855669e841b..247dcd34e52 100644
--- a/lib/tbb_2020.3/build/windows.inc
+++ b/lib/tbb_2020.3/build/windows.inc
@@ -22,15 +22,15 @@ endif
 
 # A convenience wrapper for calls to detect.js.
 # $(1) is the full command line for the script, e.g. /minversion icl 12
-detect_js = $(shell cmd //C "cscript ///NoLogo ///E:jscript $(tbb_root)/build/detect.js $(1)")
+detect_js = $(shell cmd //c "cscript //NoLogo //E:jscript $(tbb_root)/build/detect.js $(1)")
 
 # TODO give an error if archs doesn't match
 ifndef arch
-  export arch:=$(call detect_js, //arch $(compiler))
+  export arch:=$(call detect_js, /arch $(compiler))
 endif
 
 ifndef runtime
-  export runtime:=$(call detect_js, //runtime $(compiler))
+  export runtime:=$(call detect_js, /runtime $(compiler))
 endif
 
 native_compiler := cl