diff --git a/picard/file.py b/picard/file.py
index 5d99a02a1..05cfb0013 100644
--- a/picard/file.py
+++ b/picard/file.py
@@ -175,7 +175,8 @@ class File(QtCore.QObject, Item):
         deleted_tags = self.metadata.deleted_tags
         self.metadata.copy(metadata)
         if preserve_deleted:
-            self.metadata.deleted_tags = deleted_tags
+            for tag in deleted_tags:
+                self.metadata.delete(tag)
         for tag, values in saved_metadata.items():
             self.metadata.set(tag, values)
 
diff --git a/picard/metadata.py b/picard/metadata.py
index 62b45badf..5958967ca 100644
--- a/picard/metadata.py
+++ b/picard/metadata.py
@@ -301,7 +301,7 @@ class Metadata(dict):
         values = [string_(value) for value in values if value]
         if len(values):
             self.set(name, values)
-        else:
+        elif name in self:
             self.delete(name)
 
     def add(self, name, value):
diff --git a/test/test_metadata.py b/test/test_metadata.py
index 07f67ee01..71f7d6550 100644
--- a/test/test_metadata.py
+++ b/test/test_metadata.py
@@ -36,7 +36,7 @@ class MetadataTest(unittest.TestCase):
     def tearDown(self):
         pass
 
-    def test_metadata_set(self):
+    def test_metadata_setitem(self):
         self.assertEqual(["single1-value"], dict.get(self.metadata,"single1"))
         self.assertEqual(["single2-value"], dict.get(self.metadata,"single2"))
         self.assertEqual(self.multi1, dict.get(self.metadata,"multi1"))
@@ -66,10 +66,31 @@ class MetadataTest(unittest.TestCase):
         self.assertNotIn("single1", self.metadata)
         self.assertIn("single1", self.metadata.deleted_tags)
 
+    def test_metadata_implicit_delete(self):
         self.metadata["single2"] = ""
         self.assertNotIn("single2", self.metadata)
         self.assertIn("single2", self.metadata.deleted_tags)
 
+        self.metadata["unknown"] = ""
+        self.assertNotIn("unknown", self.metadata)
+        self.assertNotIn("unknown", self.metadata.deleted_tags)
+
+    def test_metadata_set_explicit_empty(self):
+        self.metadata.delete("single1")
+        self.metadata.set("single1", [])
+        self.assertIn("single1", self.metadata)
+        self.assertNotIn("single1", self.metadata.deleted_tags)
+        self.assertEqual([], self.metadata.getall("single1"))
+
+    def test_metadata_undelete(self):
+        self.metadata.delete("single1")
+        self.assertNotIn("single1", self.metadata)
+        self.assertIn("single1", self.metadata.deleted_tags)
+
+        self.metadata["single1"] = "value1"
+        self.assertIn("single1", self.metadata)
+        self.assertNotIn("single1", self.metadata.deleted_tags)
+
     def test_metadata_update(self):
         m = Metadata()
         m["old"] = "old-value"