Index: subversion/include/private/svn_wc_private.h
===================================================================
--- subversion/include/private/svn_wc_private.h	(revision 1292379)
+++ subversion/include/private/svn_wc_private.h	(working copy)
@@ -263,6 +263,15 @@
                                      apr_pool_t *result_pool,
                                      apr_pool_t *scratch_pool);
 
+/* Close the DBs for any externals under LOCAL_ABSPATH.  Detection of
+   externals is as per svn_wc__externals_gather_definitions.
+
+   Perform temporary allocations in SCRATCH_POOL. */
+svn_error_t *
+svn_wc__externals_close(const char *local_abspath,
+                        svn_wc_context_t *wc_ctx,
+                        apr_pool_t *scratch_pool);
+
 /** Set @a *tree_conflict to a newly allocated @c
  * svn_wc_conflict_description_t structure describing the tree
  * conflict state of @a victim_abspath, or to @c NULL if @a victim_abspath
Index: subversion/libsvn_client/copy.c
===================================================================
--- subversion/libsvn_client/copy.c	(revision 1292379)
+++ subversion/libsvn_client/copy.c	(working copy)
@@ -1519,6 +1519,17 @@
         ctx->notify_baton2 = old_notify_baton2;
 
         SVN_ERR(err);
+
+#ifdef WIN32
+        if (!ignore_externals)
+          {
+            /* Issue #4123: We may still hold file handles to the databases
+               for externals under TMP_ABSPATH.  We need to release these
+               handles before we move TMP_ABSPATH below or Windows will
+               raise an ERROR_ACCESS_DENIED error. */
+            SVN_ERR(svn_wc__externals_close(tmp_abspath, ctx->wc_ctx, pool));
+          }
+#endif
       }
 
       /* Schedule dst_path for addition in parent, with copy history.
Index: subversion/libsvn_wc/externals.c
===================================================================
--- subversion/libsvn_wc/externals.c	(revision 1292379)
+++ subversion/libsvn_wc/externals.c	(working copy)
@@ -1363,6 +1363,56 @@
     }
 }
 
+svn_error_t *
+svn_wc__externals_close(const char *local_abspath,
+                        svn_wc_context_t *wc_ctx,
+                        apr_pool_t *scratch_pool)
+{
+  apr_hash_t *externals;
+  apr_hash_index_t *hi;
+  apr_pool_t *iterpool;
+
+  SVN_ERR(svn_wc__externals_gather_definitions(&externals, NULL, wc_ctx,
+                                               local_abspath,
+                                               svn_depth_infinity,
+                                               scratch_pool, scratch_pool));
+
+  if (!apr_hash_count(externals))
+    return SVN_NO_ERROR;
+
+  iterpool = svn_pool_create(scratch_pool);
+      
+  for (hi = apr_hash_first(scratch_pool, externals);
+       hi;
+       hi = apr_hash_next(hi))
+    {
+      const char *this_abspath = svn__apr_hash_index_key(hi);
+      const char *external_value = svn__apr_hash_index_val(hi);
+      apr_array_header_t *ext_desc;
+      int i;
+
+      SVN_ERR(svn_wc_parse_externals_description3(&ext_desc, this_abspath,
+                                                  external_value, FALSE,
+                                                  iterpool));
+      for (i = 0; i < ext_desc->nelts; i++)
+        {
+          svn_wc_external_item2_t *ext_item =
+            APR_ARRAY_IDX(ext_desc, i, svn_wc_external_item2_t *);
+          const char *external_abspath;
+
+          SVN_ERR(svn_dirent_get_absolute(&external_abspath,
+                                          svn_dirent_join(this_abspath,
+                                                          ext_item->target_dir,
+                                                          iterpool),
+                                          iterpool));
+          SVN_ERR(svn_wc__db_drop_root(wc_ctx->db, external_abspath,
+                                       iterpool));
+        }
+    }
+  svn_pool_destroy(iterpool);
+  return SVN_NO_ERROR;
+}
+
 /* Return the scheme of @a uri in @a scheme allocated from @a pool.
    If @a uri does not appear to be a valid URI, then @a scheme will
    not be updated.  */
Index: subversion/tests/cmdline/externals_tests.py
===================================================================
--- subversion/tests/cmdline/externals_tests.py	(revision 1292379)
+++ subversion/tests/cmdline/externals_tests.py	(working copy)
@@ -2787,7 +2787,6 @@
 
 # Test for issue #4123 'URL-to-WC copy of externals fails on Windows'
 @Issue(4123)
-@XFail(svntest.main.is_os_windows)
 def url_to_wc_copy_of_externals(sbox):
   "url-to-wc copy of externals"
 
@@ -2805,7 +2804,8 @@
   svntest.actions.run_and_verify_svn(None, None, [], 'up', wc_dir)
 
   # Copy ^/A/C to External-WC-to-URL-Copy.
-  # Currently this fails with:
+  #
+  # Previously this failed with:
   #   >svn copy ^^/A/C External-WC-to-URL-Copy
   #    U   External-WC-to-URL-Copy
   #