diff --git a/Compiling-from-source.md b/Compiling-from-source.md
index 263a525..9c0e903 100644
--- a/Compiling-from-source.md
+++ b/Compiling-from-source.md
@@ -108,7 +108,7 @@ https://stackoverflow.com/questions/6951938/libgmp-10-dll-is-missing
 Your MSYS2 home directory, usually c:\msys2\home\\[windows user]\, or a directory of your choice can be used.
 
 5. Open "MSYS2 MinGW-w64" from the Windows start menu, change directories to the downloaded
-cpuminer-opt and compile.
+cpuminer-opt and compile. Add `-D_WIN32_WINNT=0x0601` to CFLAGS to enable CPU groups.
 
 `$ ./autogen.sh`