diff --git a/Lib/distutils/command/wininst-6.exe b/Lib/distutils/command/wininst-6.exe
index 8ab173b6620..efa3bc4f1f8 100644
Binary files a/Lib/distutils/command/wininst-6.exe and b/Lib/distutils/command/wininst-6.exe differ
diff --git a/Lib/distutils/command/wininst-7.1.exe b/Lib/distutils/command/wininst-7.1.exe
index 858f6f2296b..7be9396b8a9 100644
Binary files a/Lib/distutils/command/wininst-7.1.exe and b/Lib/distutils/command/wininst-7.1.exe differ
diff --git a/PC/bdist_wininst/install.c b/PC/bdist_wininst/install.c
index a715528f9ad..7ba05aaa890 100644
--- a/PC/bdist_wininst/install.c
+++ b/PC/bdist_wininst/install.c
@@ -1708,6 +1708,14 @@ InstallFilesDlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
 			hDialog = hwnd;
 			success = TRUE;
 
+			/* Disable the buttons while we work.  Sending CANCELTOCLOSE has
+			  the effect of disabling the cancel button, which is a) as we
+			  do everything synchronously we can't cancel, and b) the next
+			  step is 'finished', when it is too late to cancel anyway.
+			  The next step being 'Finished' means we also don't need to
+			  restore the button state back */
+			PropSheet_SetWizButtons(GetParent(hwnd), 0);
+			SendMessage(GetParent(hwnd), PSM_CANCELTOCLOSE, 0, 0);
 			/* Make sure the installation directory name ends in a */
 			/* backslash */
 			if (python_dir[strlen(python_dir)-1] != '\\')