diff --git a/src/lib/datasrc/memory/zone_writer.h b/src/lib/datasrc/memory/zone_writer.h
index 1fdfbfd643..6671429ba5 100644
--- a/src/lib/datasrc/memory/zone_writer.h
+++ b/src/lib/datasrc/memory/zone_writer.h
@@ -47,7 +47,7 @@ public:
     ///     discard it.
     /// \note After successful load(), you have to call cleanup() some time
     ///     later.
-    /// \throw isc::Unexpected if called second time.
+    /// \throw isc::InvalidOperation if called second time.
     virtual void load() = 0;
 
     /// \brief Put the changes to effect.
@@ -63,7 +63,7 @@ public:
     /// This may throw in rare cases, depending on the concrete implementation.
     /// If it throws, you still need to call cleanup().
     ///
-    /// \throw isc::Unexpected if called without previous load() or for the
+    /// \throw isc::InvalidOperation if called without previous load() or for the
     ///     second time or cleanup() was called already.
     virtual void install() = 0;
 
diff --git a/src/lib/datasrc/memory/zone_writer_local.cc b/src/lib/datasrc/memory/zone_writer_local.cc
index 0bccdc1560..44ff03cb5c 100644
--- a/src/lib/datasrc/memory/zone_writer_local.cc
+++ b/src/lib/datasrc/memory/zone_writer_local.cc
@@ -46,14 +46,14 @@ ZoneWriterLocal::~ZoneWriterLocal() {
 void
 ZoneWriterLocal::load() {
     if (loaded_) {
-        isc_throw(isc::Unexpected, "Trying to load twice");
+        isc_throw(isc::InvalidOperation, "Trying to load twice");
     }
 
     zone_data_ = load_action_(segment_->getMemorySegment());
 
     if (zone_data_ == NULL) {
         // Bug inside load_action_.
-        isc_throw(isc::Unexpected, "No data returned from load action");
+        isc_throw(isc::InvalidOperation, "No data returned from load action");
     }
 
     loaded_ = true;
@@ -63,13 +63,13 @@ ZoneWriterLocal::load() {
 void
 ZoneWriterLocal::install() {
     if (!data_ready_) {
-        isc_throw(isc::Unexpected, "No data to install");
+        isc_throw(isc::InvalidOperation, "No data to install");
     }
 
 
     ZoneTable* table(segment_->getHeader().getTable());
     if (table == NULL) {
-        isc_throw(isc::Unexpected, "No zone table present");
+        isc_throw(isc::InvalidOperation, "No zone table present");
     }
     ZoneTable::AddResult result(table->addZone(segment_->getMemorySegment(),
                                                rrclass_, origin_, zone_data_));
diff --git a/src/lib/datasrc/memory/zone_writer_local.h b/src/lib/datasrc/memory/zone_writer_local.h
index c0f51ed045..a106079465 100644
--- a/src/lib/datasrc/memory/zone_writer_local.h
+++ b/src/lib/datasrc/memory/zone_writer_local.h
@@ -53,7 +53,7 @@ public:
     /// This calls the load_action (passed to constructor) and stores the
     /// data for future use.
     ///
-    /// \throw isc::Unexpected if it is called the second time in lifetime
+    /// \throw isc::InvalidOperation if it is called the second time in lifetime
     ///     of the object.
     /// \throw Whatever the load_action throws, it is propagated up.
     virtual void load();
@@ -63,7 +63,7 @@ public:
     /// It modifies the zone table accessible through the segment (passed to
     /// constructor).
     ///
-    /// \throw isc::Unexpected if it is called the second time in lifetime
+    /// \throw isc::InvalidOperation if it is called the second time in lifetime
     ///     of the object or if load() was not called previously or if
     ///     cleanup() was already called.
     virtual void install();
diff --git a/src/lib/datasrc/tests/memory/zone_writer_unittest.cc b/src/lib/datasrc/tests/memory/zone_writer_unittest.cc
index dea093b8e3..bffcde5585 100644
--- a/src/lib/datasrc/tests/memory/zone_writer_unittest.cc
+++ b/src/lib/datasrc/tests/memory/zone_writer_unittest.cc
@@ -118,7 +118,7 @@ TEST_F(ZoneWriterLocalTest, loadTwice) {
     load_called_ = false;
 
     // The second time, it should not be possible
-    EXPECT_THROW(writer_->load(), isc::Unexpected);
+    EXPECT_THROW(writer_->load(), isc::InvalidOperation);
     EXPECT_FALSE(load_called_);
 
     // The object should not be damaged, try installing and clearing now
@@ -139,20 +139,20 @@ TEST_F(ZoneWriterLocalTest, loadLater) {
     // Reset so we see nothing is called now
     load_called_ = false;
 
-    EXPECT_THROW(writer_->load(), isc::Unexpected);
+    EXPECT_THROW(writer_->load(), isc::InvalidOperation);
     EXPECT_FALSE(load_called_);
 
     // Cleanup and try loading again. Still shouldn't work.
     EXPECT_NO_THROW(writer_->cleanup());
 
-    EXPECT_THROW(writer_->load(), isc::Unexpected);
+    EXPECT_THROW(writer_->load(), isc::InvalidOperation);
     EXPECT_FALSE(load_called_);
 }
 
 // Try calling install at various bad times
 TEST_F(ZoneWriterLocalTest, invalidInstall) {
     // Nothing loaded yet
-    EXPECT_THROW(writer_->install(), isc::Unexpected);
+    EXPECT_THROW(writer_->install(), isc::InvalidOperation);
     EXPECT_FALSE(load_called_);
 
     EXPECT_NO_THROW(writer_->load());
@@ -160,7 +160,7 @@ TEST_F(ZoneWriterLocalTest, invalidInstall) {
     // This install is OK
     EXPECT_NO_THROW(writer_->install());
     // But we can't call it second time now
-    EXPECT_THROW(writer_->install(), isc::Unexpected);
+    EXPECT_THROW(writer_->install(), isc::InvalidOperation);
     EXPECT_FALSE(load_called_);
 }
 
@@ -174,7 +174,7 @@ TEST_F(ZoneWriterLocalTest, cleanWithoutInstall) {
     EXPECT_TRUE(load_called_);
 
     // We cleaned up, no way to install now
-    EXPECT_THROW(writer_->install(), isc::Unexpected);
+    EXPECT_THROW(writer_->install(), isc::InvalidOperation);
 }
 
 // Test the case when load callback throws
@@ -183,7 +183,7 @@ TEST_F(ZoneWriterLocalTest, loadThrows) {
     EXPECT_THROW(writer_->load(), TestException);
 
     // We can't install now
-    EXPECT_THROW(writer_->install(), isc::Unexpected);
+    EXPECT_THROW(writer_->install(), isc::InvalidOperation);
     EXPECT_TRUE(load_called_);
 
     // But we can cleanup
@@ -208,10 +208,10 @@ TEST_F(ZoneWriterLocalTest, retry) {
 // Check the writer defends itsefl when load action returns NULL
 TEST_F(ZoneWriterLocalTest, loadNull) {
     load_null_ = true;
-    EXPECT_THROW(writer_->load(), isc::Unexpected);
+    EXPECT_THROW(writer_->load(), isc::InvalidOperation);
 
     // We can't install that
-    EXPECT_THROW(writer_->install(), isc::Unexpected);
+    EXPECT_THROW(writer_->install(), isc::InvalidOperation);
 
     // It should be possible to clean up safely
     EXPECT_NO_THROW(writer_->cleanup());