Index: src/ch/ch.cpp
===================================================================
diff -u -N -r1beb1d8feacc2517287b975f27ad5f521fa1c954 -r787ecfe9fd8f4f349d47b491ed507796f257595d
--- src/ch/ch.cpp	(.../ch.cpp)	(revision 1beb1d8feacc2517287b975f27ad5f521fa1c954)
+++ src/ch/ch.cpp	(.../ch.cpp)	(revision 787ecfe9fd8f4f349d47b491ed507796f257595d)
@@ -320,7 +320,7 @@
 	if(uiPropID == PP_PHELPDIR)
 	{
 		if(UpdateHelpPaths())
-			HtmlHelp(HH_CLOSE_ALL, NULL);
+			HtmlHelp(NULL, HH_CLOSE_ALL);
 	}
 }
 
@@ -330,7 +330,7 @@
 	{
 		// language has been changed - close the current help file
 		if (UpdateHelpPaths())
-			HtmlHelp(HH_CLOSE_ALL, NULL);
+			HtmlHelp(NULL, HH_CLOSE_ALL);
 	}
 }
 
@@ -359,7 +359,7 @@
 		return ::HtmlHelp(hwndCaller, pszPath, uCommand, dwData);
 }
 
-void CCopyHandlerApp::HtmlHelp(UINT nCmd, DWORD_PTR dwData)
+void CCopyHandlerApp::HtmlHelp(DWORD_PTR dwData, UINT nCmd)
 {
 	switch (nCmd)
 	{