diff --git a/Contrib/ExDLL/exdll.h b/Contrib/ExDLL/exdll.h
index bbccafb0..6d3f0b9d 100644
--- a/Contrib/ExDLL/exdll.h
+++ b/Contrib/ExDLL/exdll.h
@@ -1,102 +1,15 @@
+// this file is for backward compatibility only
+// use the new plugin.h and plugin.lib directly for new plug-ins
+
 #ifndef _EXDLL_H_
 #define _EXDLL_H_
 
 #include <windows.h>
-#include "../../Source/exehead/api.h"
+#include <plugin.h> // nsis plugin.h
 
-#if defined(__GNUC__)
-#define UNUSED __attribute__((unused))
-#else
-#define UNUSED
+// this may not work if /NODEFAULTLIB is used
+#ifdef _MSC_VER
+#  pragma comment(lib, "plugin.lib")
 #endif
 
-// only include this file from one place in your DLL.
-// (it is all static, if you use it in two places it will fail)
-
-#define EXDLL_INIT()           {  \
-        g_stringsize=string_size; \
-        g_stacktop=stacktop;      \
-        g_variables=variables; }
-
-typedef struct _stack_t {
-  struct _stack_t *next;
-  char text[1]; // this should be the length of string_size
-} stack_t;
-
-
-static unsigned int g_stringsize;
-static stack_t **g_stacktop;
-static char *g_variables;
-
-static int __stdcall popstring(char *str) UNUSED; // 0 on success, 1 on empty stack
-static void __stdcall pushstring(const char *str) UNUSED;
-static char * __stdcall getuservariable(const int varnum) UNUSED;
-static void __stdcall setuservariable(const int varnum, const char *var) UNUSED;
-
-enum
-{
-INST_0,         // $0
-INST_1,         // $1
-INST_2,         // $2
-INST_3,         // $3
-INST_4,         // $4
-INST_5,         // $5
-INST_6,         // $6
-INST_7,         // $7
-INST_8,         // $8
-INST_9,         // $9
-INST_R0,        // $R0
-INST_R1,        // $R1
-INST_R2,        // $R2
-INST_R3,        // $R3
-INST_R4,        // $R4
-INST_R5,        // $R5
-INST_R6,        // $R6
-INST_R7,        // $R7
-INST_R8,        // $R8
-INST_R9,        // $R9
-INST_CMDLINE,   // $CMDLINE
-INST_INSTDIR,   // $INSTDIR
-INST_OUTDIR,    // $OUTDIR
-INST_EXEDIR,    // $EXEDIR
-INST_LANG,      // $LANGUAGE
-__INST_LAST
-};
-
-// utility functions (not required but often useful)
-static int __stdcall popstring(char *str)
-{
-  stack_t *th;
-  if (!g_stacktop || !*g_stacktop) return 1;
-  th=(*g_stacktop);
-  lstrcpyA(str,th->text);
-  *g_stacktop = th->next;
-  GlobalFree((HGLOBAL)th);
-  return 0;
-}
-
-static void __stdcall pushstring(const char *str)
-{
-  stack_t *th;
-  if (!g_stacktop) return;
-  th=(stack_t*)GlobalAlloc(GPTR,sizeof(stack_t)+g_stringsize);
-  lstrcpynA(th->text,str,g_stringsize);
-  th->next=*g_stacktop;
-  *g_stacktop=th;
-}
-
-static char * __stdcall getuservariable(const int varnum)
-{
-  if (varnum < 0 || varnum >= __INST_LAST) return NULL;
-  return g_variables+varnum*g_stringsize;
-}
-
-static void __stdcall setuservariable(const int varnum, const char *var)
-{
-	if (var != NULL && varnum >= 0 && varnum < __INST_LAST) 
-		lstrcpyA(g_variables + varnum*g_stringsize, var);
-}
-
-
-
 #endif//_EXDLL_H_