diff --git a/src/core/iomgr/sockaddr_utils.c b/src/core/iomgr/sockaddr_utils.c
index 07bf7b3..8dcfca7 100644
--- a/src/core/iomgr/sockaddr_utils.c
+++ b/src/core/iomgr/sockaddr_utils.c
@@ -111,13 +111,20 @@
 
 void grpc_sockaddr_make_wildcards(int port, struct sockaddr_in *wild4_out,
                                   struct sockaddr_in6 *wild6_out) {
-  memset(wild4_out, 0, sizeof(*wild4_out));
-  wild4_out->sin_family = AF_INET;
-  wild4_out->sin_port = htons(port);
+  grpc_sockaddr_make_wildcard4(port, wild4_out);
+  grpc_sockaddr_make_wildcard6(port, wild6_out);
+}
 
-  memset(wild6_out, 0, sizeof(*wild6_out));
-  wild6_out->sin6_family = AF_INET6;
-  wild6_out->sin6_port = htons(port);
+void grpc_sockaddr_make_wildcard4(int port, struct sockaddr_in *wild_out) {
+  memset(wild_out, 0, sizeof(*wild_out));
+  wild_out->sin_family = AF_INET;
+  wild_out->sin_port = htons(port);
+}
+
+void grpc_sockaddr_make_wildcard6(int port, struct sockaddr_in6 *wild_out) {
+  memset(wild_out, 0, sizeof(*wild_out));
+  wild_out->sin6_family = AF_INET6;
+  wild_out->sin6_port = htons(port);
 }
 
 int grpc_sockaddr_to_string(char **out, const struct sockaddr *addr,
diff --git a/src/core/iomgr/sockaddr_utils.h b/src/core/iomgr/sockaddr_utils.h
index 3f5b770..b49cc50 100644
--- a/src/core/iomgr/sockaddr_utils.h
+++ b/src/core/iomgr/sockaddr_utils.h
@@ -57,6 +57,12 @@
 void grpc_sockaddr_make_wildcards(int port, struct sockaddr_in *wild4_out,
                                   struct sockaddr_in6 *wild6_out);
 
+/* Writes 0.0.0.0:port. */
+void grpc_sockaddr_make_wildcard4(int port, struct sockaddr_in *wild_out);
+
+/* Writes [::]:port. */
+void grpc_sockaddr_make_wildcard6(int port, struct sockaddr_in6 *wild_out);
+
 /* Return the IP port number of a sockaddr */
 int grpc_sockaddr_get_port(const struct sockaddr *addr);
 
diff --git a/src/core/iomgr/tcp_client_windows.c b/src/core/iomgr/tcp_client_windows.c
index 465fc75..37e6b12 100644
--- a/src/core/iomgr/tcp_client_windows.c
+++ b/src/core/iomgr/tcp_client_windows.c
@@ -106,9 +106,7 @@
       goto finish;
     }
   } else {
-    __debugbreak();
-    abort();
-    gpr_log(GPR_ERROR, "on_writable failed during connect");
+    gpr_log(GPR_ERROR, "on_connect is shutting down");
     goto finish;
   }
 
@@ -167,9 +165,7 @@
     goto failure;
   }
 
-  memset(&local_address, 0, sizeof(local_address));
-  memcpy(&local_address.sin6_addr, &in6addr_any, sizeof(in6addr_any));
-  local_address.sin6_family = AF_INET6;
+  grpc_sockaddr_make_wildcard6(0, &local_address);
 
   status = bind(sock, (struct sockaddr *) &local_address,
                 sizeof(local_address));
diff --git a/src/core/iomgr/tcp_server_windows.c b/src/core/iomgr/tcp_server_windows.c
new file mode 100644
index 0000000..2190195
--- /dev/null
+++ b/src/core/iomgr/tcp_server_windows.c
@@ -0,0 +1,372 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#ifdef GPR_WINSOCK_SOCKET
+
+#define _GNU_SOURCE
+#include "src/core/iomgr/sockaddr_utils.h"
+
+#include "src/core/iomgr/pollset_windows.h"
+#include "src/core/iomgr/socket_windows.h"
+#include "src/core/iomgr/tcp_server.h"
+#include "src/core/iomgr/tcp_windows.h"
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/log_win32.h>
+#include <grpc/support/sync.h>
+#include <grpc/support/time.h>
+
+#define INIT_PORT_CAP 2
+#define MIN_SAFE_ACCEPT_QUEUE_SIZE 100
+
+static gpr_once s_init_max_accept_queue_size;
+static int s_max_accept_queue_size;
+
+/* one listening port */
+typedef struct server_port {
+  gpr_uint8 addresses[sizeof(struct sockaddr_in6) * 2 + 32];
+  SOCKET new_socket;
+  grpc_winsocket *socket;
+  grpc_tcp_server *server;
+  LPFN_ACCEPTEX AcceptEx;
+} server_port;
+
+/* the overall server */
+struct grpc_tcp_server {
+  grpc_tcp_server_cb cb;
+  void *cb_arg;
+
+  gpr_mu mu;
+  gpr_cv cv;
+
+  /* active port count: how many ports are actually still listening */
+  int active_ports;
+
+  /* all listening ports */
+  server_port *ports;
+  size_t nports;
+  size_t port_capacity;
+};
+
+grpc_tcp_server *grpc_tcp_server_create(void) {
+  grpc_tcp_server *s = gpr_malloc(sizeof(grpc_tcp_server));
+  gpr_mu_init(&s->mu);
+  gpr_cv_init(&s->cv);
+  s->active_ports = 0;
+  s->cb = NULL;
+  s->cb_arg = NULL;
+  s->ports = gpr_malloc(sizeof(server_port) * INIT_PORT_CAP);
+  s->nports = 0;
+  s->port_capacity = INIT_PORT_CAP;
+  return s;
+}
+
+void grpc_tcp_server_destroy(grpc_tcp_server *s) {
+  size_t i;
+  gpr_mu_lock(&s->mu);
+  /* shutdown all fd's */
+  for (i = 0; i < s->nports; i++) {
+    grpc_winsocket_shutdown(s->ports[i].socket);
+  }
+  /* wait while that happens */
+  while (s->active_ports) {
+    gpr_cv_wait(&s->cv, &s->mu, gpr_inf_future);
+  }
+  gpr_mu_unlock(&s->mu);
+
+  /* delete ALL the things */
+  for (i = 0; i < s->nports; i++) {
+    server_port *sp = &s->ports[i];
+    grpc_winsocket_orphan(sp->socket);
+  }
+  gpr_free(s->ports);
+  gpr_free(s);
+}
+
+/* Prepare a recently-created socket for listening. */
+static int prepare_socket(SOCKET sock,
+                          const struct sockaddr *addr, int addr_len) {
+  struct sockaddr_storage sockname_temp;
+  socklen_t sockname_len;
+
+  if (sock == INVALID_SOCKET) goto error;
+
+  if (!grpc_tcp_prepare_socket(sock)) {
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    gpr_log(GPR_ERROR, "Unable to prepare socket: %s", utf8_message);
+    gpr_free(utf8_message);
+    goto error;
+  }
+
+  if (bind(sock, addr, addr_len) == SOCKET_ERROR) {
+    char *addr_str;
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    grpc_sockaddr_to_string(&addr_str, addr, 0);
+    gpr_log(GPR_ERROR, "bind addr=%s: %s", addr_str, utf8_message);
+    gpr_free(utf8_message);
+    gpr_free(addr_str);
+    goto error;
+  }
+
+  if (listen(sock, SOMAXCONN) == SOCKET_ERROR) {
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    gpr_log(GPR_ERROR, "listen: %s", utf8_message);
+    gpr_free(utf8_message);
+    goto error;
+  }
+
+  sockname_len = sizeof(sockname_temp);
+  if (getsockname(sock, (struct sockaddr *) &sockname_temp, &sockname_len)
+        == SOCKET_ERROR) {
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    gpr_log(GPR_ERROR, "getsockname: %s", utf8_message);
+    gpr_free(utf8_message);
+    goto error;
+  }
+
+  return grpc_sockaddr_get_port((struct sockaddr *) &sockname_temp);
+
+error:
+  if (sock != INVALID_SOCKET) closesocket(sock);
+  return -1;
+}
+
+static void on_accept(void *arg, int success);
+
+static void start_accept(server_port *port) {
+  SOCKET sock = INVALID_SOCKET;
+  char *message;
+  char *utf8_message;
+  BOOL success;
+  DWORD addrlen = sizeof(struct sockaddr_in6) + 16;
+  DWORD bytes_received = 0;
+
+  sock = WSASocket(AF_INET6, SOCK_STREAM, IPPROTO_TCP, NULL, 0,
+                   WSA_FLAG_OVERLAPPED);
+
+  if (sock == INVALID_SOCKET) {
+    message = "Unable to create socket: %s";
+    goto failure;
+  }
+
+  if (!grpc_tcp_prepare_socket(sock)) {
+    message = "Unable to prepare socket: %s";
+    goto failure;
+  }
+
+  success = port->AcceptEx(port->socket->socket, sock, port->addresses, 0,
+                           addrlen, addrlen, &bytes_received,
+                           &port->socket->read_info.overlapped);
+
+  if (success) {
+    gpr_log(GPR_DEBUG, "accepted immediately - but we still go to sleep");
+  } else {
+    int error = WSAGetLastError();
+    if (error != ERROR_IO_PENDING) {
+      message = "AcceptEx failed: %s";
+      goto failure;
+    }
+  }
+
+  port->new_socket = sock;
+  grpc_handle_notify_on_read(port->socket, on_accept, port);
+  return;
+
+failure:
+  utf8_message = gpr_format_message(WSAGetLastError());
+  gpr_log(GPR_ERROR, message, utf8_message);
+  gpr_free(utf8_message);
+  if (sock != INVALID_SOCKET) closesocket(sock);
+}
+
+/* event manager callback when reads are ready */
+static void on_accept(void *arg, int success) {
+  server_port *sp = arg;
+  SOCKET sock = sp->new_socket;
+  grpc_winsocket_callback_info *info = &sp->socket->read_info;
+  grpc_endpoint *ep = NULL;
+
+  if (success) {
+    DWORD transfered_bytes = 0;
+    DWORD flags;
+    BOOL wsa_success = WSAGetOverlappedResult(sock, &info->overlapped,
+                                              &transfered_bytes, FALSE,
+                                              &flags);
+    if (!wsa_success) {
+      char *utf8_message = gpr_format_message(WSAGetLastError());
+      gpr_log(GPR_ERROR, "on_accept error: %s", utf8_message);
+      gpr_free(utf8_message);
+      closesocket(sock);
+    } else {
+      gpr_log(GPR_DEBUG, "on_accept: accepted connection");
+      ep = grpc_tcp_create(grpc_winsocket_create(sock));
+    }
+  } else {
+    gpr_log(GPR_DEBUG, "on_accept: shutting down");
+    closesocket(sock);
+    gpr_mu_lock(&sp->server->mu);
+    if (0 == --sp->server->active_ports) {
+      gpr_cv_broadcast(&sp->server->cv);
+    }
+    gpr_mu_unlock(&sp->server->mu);
+  }
+
+  if (ep) sp->server->cb(sp->server->cb_arg, ep);
+  start_accept(sp);
+}
+
+static int add_socket_to_server(grpc_tcp_server *s, SOCKET sock,
+                                const struct sockaddr *addr, int addr_len) {
+  server_port *sp;
+  int port;
+  int status;
+  GUID guid = WSAID_ACCEPTEX;
+  DWORD ioctl_num_bytes;
+  LPFN_ACCEPTEX AcceptEx;
+
+  if (sock == INVALID_SOCKET) return -1;
+
+  status = WSAIoctl(sock, SIO_GET_EXTENSION_FUNCTION_POINTER,
+                    &guid, sizeof(guid), &AcceptEx, sizeof(AcceptEx),
+                    &ioctl_num_bytes, NULL, NULL);
+
+  if (status != 0) {
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    gpr_log(GPR_ERROR, "on_connect error: %s", utf8_message);
+    gpr_free(utf8_message);
+    closesocket(sock);
+    return -1;
+  }
+
+  port = prepare_socket(sock, addr, addr_len);
+  if (port >= 0) {
+    gpr_mu_lock(&s->mu);
+    GPR_ASSERT(!s->cb && "must add ports before starting server");
+    /* append it to the list under a lock */
+    if (s->nports == s->port_capacity) {
+      s->port_capacity *= 2;
+      s->ports = gpr_realloc(s->ports, sizeof(server_port) * s->port_capacity);
+    }
+    sp = &s->ports[s->nports++];
+    sp->server = s;
+    sp->socket = grpc_winsocket_create(sock);
+    sp->AcceptEx = AcceptEx;
+    GPR_ASSERT(sp->socket);
+    gpr_mu_unlock(&s->mu);
+  }
+
+  return port;
+}
+
+int grpc_tcp_server_add_port(grpc_tcp_server *s, const void *addr,
+                             int addr_len) {
+  int allocated_port = -1;
+  unsigned i;
+  SOCKET sock;
+  struct sockaddr_in6 addr6_v4mapped;
+  struct sockaddr_in6 wildcard;
+  struct sockaddr *allocated_addr = NULL;
+  struct sockaddr_storage sockname_temp;
+  socklen_t sockname_len;
+  int port;
+
+  /* Check if this is a wildcard port, and if so, try to keep the port the same
+     as some previously created listener. */
+  if (grpc_sockaddr_get_port(addr) == 0) {
+    for (i = 0; i < s->nports; i++) {
+      sockname_len = sizeof(sockname_temp);
+      if (0 == getsockname(s->ports[i].socket->socket,
+                           (struct sockaddr *) &sockname_temp,
+                           &sockname_len)) {
+        port = grpc_sockaddr_get_port((struct sockaddr *) &sockname_temp);
+        if (port > 0) {
+          allocated_addr = malloc(addr_len);
+          memcpy(allocated_addr, addr, addr_len);
+          grpc_sockaddr_set_port(allocated_addr, port);
+          addr = allocated_addr;
+          break;
+        }
+      }
+    }
+  }
+
+  if (grpc_sockaddr_to_v4mapped(addr, &addr6_v4mapped)) {
+    addr = (const struct sockaddr *)&addr6_v4mapped;
+    addr_len = sizeof(addr6_v4mapped);
+  }
+
+  /* Treat :: or 0.0.0.0 as a family-agnostic wildcard. */
+  if (grpc_sockaddr_is_wildcard(addr, &port)) {
+    grpc_sockaddr_make_wildcard6(port, &wildcard);
+
+    addr = (struct sockaddr *) &wildcard;
+    addr_len = sizeof(wildcard);
+  }
+
+  sock = WSASocket(AF_INET6, SOCK_STREAM, IPPROTO_TCP, NULL, 0,
+                   WSA_FLAG_OVERLAPPED);
+  if (sock == INVALID_SOCKET) {
+    char *utf8_message = gpr_format_message(WSAGetLastError());
+    gpr_log(GPR_ERROR, "unable to create socket: %s", utf8_message);
+    gpr_free(utf8_message);
+  }
+
+  allocated_port = add_socket_to_server(s, sock, addr, addr_len);
+  gpr_free(allocated_addr);
+
+  return allocated_port;
+}
+
+SOCKET grpc_tcp_server_get_socket(grpc_tcp_server *s, unsigned index) {
+  return (index < s->nports) ? s->ports[index].socket->socket : INVALID_SOCKET;
+}
+
+void grpc_tcp_server_start(grpc_tcp_server *s, grpc_pollset *pollset,
+                           grpc_tcp_server_cb cb, void *cb_arg) {
+  size_t i;
+  GPR_ASSERT(cb);
+  gpr_mu_lock(&s->mu);
+  GPR_ASSERT(!s->cb);
+  GPR_ASSERT(s->active_ports == 0);
+  s->cb = cb;
+  s->cb_arg = cb_arg;
+  for (i = 0; i < s->nports; i++) {
+    start_accept(s->ports + i);
+    s->active_ports++;
+  }
+  gpr_mu_unlock(&s->mu);
+}
+
+#endif  /* GPR_WINSOCK_SOCKET */
diff --git a/src/core/iomgr/tcp_windows.c b/src/core/iomgr/tcp_windows.c
index 734628d..bd0b2dd 100644
--- a/src/core/iomgr/tcp_windows.c
+++ b/src/core/iomgr/tcp_windows.c
@@ -61,7 +61,8 @@
 static int set_dualstack(SOCKET sock) {
   int status;
   unsigned long param = 0;
-  status = setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &param, sizeof(param));
+  status = setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
+                      (const char *) &param, sizeof(param));
   return status == 0;
 }
 
@@ -120,7 +121,7 @@
 
   if (!success) {
     tcp_unref(tcp);
-    cb(opaque, NULL, 0, GRPC_ENDPOINT_CB_SHUTDOWN);
+    cb(opaque, GRPC_ENDPOINT_CB_SHUTDOWN);
     return;
   }