diff --git a/src/openvpn/init.c b/src/openvpn/init.c
index 622239f6b10..32211f11e53 100644
--- a/src/openvpn/init.c
+++ b/src/openvpn/init.c
@@ -1850,7 +1850,8 @@ do_open_tun(struct context *c, int *error_flags)
 #ifdef _WIN32
         /* store (hide) interactive service handle in tuntap_options */
         c->c1.tuntap->options.msg_channel = c->options.msg_channel;
-        msg(D_ROUTE, "interactive service msg_channel=%" PRIu64, (unsigned long long) c->options.msg_channel);
+        msg(D_ROUTE, "interactive service msg_channel=%" PRIuPTR,
+            (intptr_t) c->options.msg_channel);
 #endif
 
         /* allocate route list structure */
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 9105449c7f8..2e41eea4e2c 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -7876,7 +7876,7 @@ add_option(struct options *options,
 #ifdef _WIN32
         VERIFY_PERMISSION(OPT_P_GENERAL);
         HANDLE process = GetCurrentProcess();
-        HANDLE handle = (HANDLE) atoll(p[1]);
+        HANDLE handle = (HANDLE) ((intptr_t) atoll(p[1]));
         if (!DuplicateHandle(process, handle, process, &options->msg_channel, 0,
                              FALSE, DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS))
         {