diff --git a/lib/isc/win32/ltdl.h b/lib/isc/win32/ltdl.h
new file mode 100644
index 0000000000..16beb862ea
--- /dev/null
+++ b/lib/isc/win32/ltdl.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#pragma once
+
+#include <windows.h>
+
+#define lt_dlhandle    HMODULE
+#define lt_dlinit()    ISC_R_SUCCESS
+#define lt_dlopen(f)   LoadLibraryW(f)
+#define lt_dlsym(h, s) GetProcAddress(h, s)
+#define lt_dlclose(h)  FreeLibrary(h)
+
+_Thread_local LPSTR __dlerror_message[1024] = { 0 };
+
+static const char *
+lt_dlerror(void) {
+	DWORD errorMessageID = GetLastError();
+	if (errorMessageID == 0) {
+		return (NULL);
+	}
+
+	LPSTR messageBuffer = NULL;
+	size_t size = FormatMessageA(
+		FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
+			FORMAT_MESSAGE_IGNORE_INSERTS,
+		NULL, errorMessageID, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+		(LPSTR)&messageBuffer, 0, NULL);
+
+	strlcpy(__dlerror_message, messageBuffer, sizeof(__dlerror_message));
+
+	LocalFree(messageBuffer);
+
+	return ((const char *)__dlerror_message);
+}
diff --git a/util/copyrights b/util/copyrights
index ee53272280..119596c90b 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -2031,6 +2031,7 @@
 ./lib/isc/win32/libisc.vcxproj.filters.in	X	2013,2014,2015,2016,2018,2019,2020
 ./lib/isc/win32/libisc.vcxproj.in		X	2013,2014,2015,2016,2017,2018,2019,2020
 ./lib/isc/win32/libisc.vcxproj.user		X	2013,2018,2019,2020
+./lib/isc/win32/ltdl.h				C	2020
 ./lib/isc/win32/meminfo.c			C	2015,2016,2018,2019,2020
 ./lib/isc/win32/net.c				C	1999,2000,2001,2002,2003,2004,2005,2007,2008,2009,2011,2012,2013,2014,2015,2016,2018,2019,2020
 ./lib/isc/win32/netdb.h				C	2000,2001,2004,2006,2007,2009,2013,2016,2018,2019,2020