1 files changed, 1 insertions, 1 deletions

diff --git a/src/w32term.c b/src/w32term.c
index 7e9c78dde33..ea539a0a1b7 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -2627,7 +2627,7 @@ w32_read_socket (sd, bufp, numchars, waitp, expected)
           
           break;
         case WM_SYSCOMMAND:
-          switch (msg.msg.wParam) 
+          switch (msg.msg.wParam & 0xfff0)  /* Lower 4 bits used by Windows. */
             {
             case SC_CLOSE:
               f = x_window_to_frame (dpyinfo, msg.msg.hwnd);