diff --git a/src/support/os_cygwin.cpp b/src/support/os_cygwin.cpp
index c2bdb387a6..702d67f418 100644
--- a/src/support/os_cygwin.cpp
+++ b/src/support/os_cygwin.cpp
@@ -456,19 +456,14 @@ bool autoOpenFile(string const & filename, auto_open_mode const mode,
 		cygwin_internal(CW_SYNC_WINENV);
 	}
 
-	string win_path;
-	try {
-		win_path = to_local8bit(from_utf8(convert_path(filename, PathStyle(windows))));
-	} catch (...) {
-		LYXERR0("Cannot encode file name `" << filename << "' to local 8 bit encoding");
-		return false;
-	}
-
+	QString const win_path =
+		toqstr(convert_path(filename, PathStyle(windows)));
 
 	// reference: http://msdn.microsoft.com/en-us/library/bb762153.aspx
-	char const * action = (mode == VIEW) ? "open" : "edit";
-	bool success = reinterpret_cast<long>(ShellExecute(NULL, action,
-					win_path.c_str(), NULL, NULL, 1)) > 32;
+	wchar_t const * action = (mode == VIEW) ? L"open" : L"edit";
+	bool success = reinterpret_cast<long>(ShellExecuteW(NULL, action,
+			reinterpret_cast<wchar_t const *>(win_path.utf16()),
+			NULL, NULL, 1)) > 32;
 
 	if (!path.empty() && !lyxrc.texinputs_prefix.empty()) {
 		setEnv("TEXINPUTS", oldtexinputs);
diff --git a/src/support/os_win32.cpp b/src/support/os_win32.cpp
index e947b7f42b..a5b5bbe825 100644
--- a/src/support/os_win32.cpp
+++ b/src/support/os_win32.cpp
@@ -567,18 +567,13 @@ bool autoOpenFile(string const & filename, auto_open_mode const mode,
 		setEnv("TEXFONTS", newtexfonts);
 	}
 
-	string fname8;
-	try {
-		fname8 = to_local8bit(from_utf8(filename));
-	} catch (...) {
-		LYXERR0("Cannot encode file name `" << filename << "' to local 8 bit encoding");
-		return false;
-	}
+	QString const wname = toqstr(filename);
 
 	// reference: http://msdn.microsoft.com/en-us/library/bb762153.aspx
-	char const * action = (mode == VIEW) ? "open" : "edit";
-	bool success = reinterpret_cast<intptr_t>(ShellExecute(NULL, action,
-		fname8.c_str(), NULL, NULL, 1)) > 32;
+	wchar_t const * action = (mode == VIEW) ? L"open" : L"edit";
+	bool success = reinterpret_cast<intptr_t>(ShellExecuteW(NULL, action,
+			reinterpret_cast<wchar_t const *>(wname.utf16()),
+			NULL, NULL, 1)) > 32;
 
 	if (!path.empty() && !lyxrc.texinputs_prefix.empty()) {
 		setEnv("TEXINPUTS", oldtexinputs);