diff --git a/scd/app.c b/scd/app.c
index c2ff50285..ebba472c2 100644
--- a/scd/app.c
+++ b/scd/app.c
@@ -2460,16 +2460,6 @@ app_check_pin (card_t card, ctrl_t ctrl, const char *keyidstr,
   return err;
 }
 
-#ifndef HAVE_W32_SYSTEM
-static void
-setup_env (void *arg)
-{
-  char *v = arg;
-
-  putenv (v);
-}
-#endif
-
 static void
 report_change (int slot, int old_status, int cur_status)
 {
@@ -2492,7 +2482,13 @@ report_change (int slot, int old_status, int cur_status)
   xfree (fname);
 
   homestr = make_filename (gnupg_homedir (), NULL);
+#ifdef HAVE_W32_SYSTEM
+  /* An environment block is terminated by two/four zero bytes.  It's
+   * four zero bytes for Unicode.  Let us always use four zero bytes.  */
+  if (gpgrt_asprintf (&envstr, "GNUPGHOME=%s%c%c%c", homestr, 0, 0, 0) < 0)
+#else
   if (gpgrt_asprintf (&envstr, "GNUPGHOME=%s", homestr) < 0)
+#endif
     log_error ("out of core while building environment\n");
   else
     {
@@ -2520,8 +2516,11 @@ report_change (int slot, int old_status, int cur_status)
       err = gpgrt_spawn_actions_new (&act);
       if (!err)
         {
-#ifndef HAVE_W32_SYSTEM
-          gpgrt_spawn_actions_set_atfork (act, setup_env, envstr);
+#ifdef HAVE_W32_SYSTEM
+          gpgrt_spawn_actions_set_envvars (act, envstr);
+#else
+          char *env[2] = { envstr, NULL };
+          gpgrt_spawn_actions_set_environ (act, env);
 #endif
           err = gpgrt_process_spawn (fname, args, GPGRT_PROCESS_DETACHED,
                                      act, NULL);