diff --git a/test/cbmc/proofs/make_proof_makefiles.py b/test/cbmc/proofs/make_proof_makefiles.py
index 16f2a0204..838629041 100755
--- a/test/cbmc/proofs/make_proof_makefiles.py
+++ b/test/cbmc/proofs/make_proof_makefiles.py
@@ -121,7 +121,7 @@ def prolog():
 
                 On Windows ->
 
-                H_INC = /Imy\cool\directory
+                H_INC = /Imy\\cool\\directory
                 H_DEF = /DHALF=/2
 
         When invoked, this script walks the directory tree looking for files