diff --git a/src/main/java/com/erudika/para/server/persistence/MongoDBDAO.java b/src/main/java/com/erudika/para/server/persistence/MongoDBDAO.java
index 54be20c..1d88bbd 100644
--- a/src/main/java/com/erudika/para/server/persistence/MongoDBDAO.java
+++ b/src/main/java/com/erudika/para/server/persistence/MongoDBDAO.java
@@ -43,6 +43,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
@@ -206,7 +207,7 @@ public <P extends ParaObject> void createAll(String appid, List<P> objects) {
 		}
 		try {
 			List<Document> documents = new ArrayList<Document>();
-			for (ParaObject so : objects) {
+			for (ParaObject so : new LinkedHashSet<>(objects)) { // fix duplicate _id errors by using a set
 				if (so != null) {
 					if (StringUtils.isBlank(so.getId())) {
 						so.setId(MongoDBUtils.generateNewId());
diff --git a/src/test/java/com/erudika/para/server/persistence/MongoDBDAOIT.java b/src/test/java/com/erudika/para/server/persistence/MongoDBDAOIT.java
index 76e3d46..b1ebfde 100644
--- a/src/test/java/com/erudika/para/server/persistence/MongoDBDAOIT.java
+++ b/src/test/java/com/erudika/para/server/persistence/MongoDBDAOIT.java
@@ -17,12 +17,12 @@
  */
 package com.erudika.para.server.persistence;
 
-import com.erudika.para.server.persistence.MongoDBDAO;
-import com.erudika.para.server.persistence.MongoDBUtils;
 import com.erudika.para.core.Sysprop;
+import java.util.List;
 import org.junit.AfterClass;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import org.junit.BeforeClass;
@@ -130,4 +130,34 @@ public void testFieldNameSanitization() {
 		d.delete(s1);
 	}
 
+	@Test
+	public void testInsertManyWithIdDuplication() {
+		MongoDBDAO d = ((MongoDBDAO) dao());
+		Sysprop s1 = new Sysprop("id:one");
+		Sysprop s2 = new Sysprop("id:two");
+		Sysprop s3 = new Sysprop("id:two");
+		Sysprop s4 = new Sysprop("id:three");
+
+		d.createAll(List.of(s1, s2, s3, s4));
+
+		assertNotNull(d.read(s1.getId()));
+		assertNotNull(d.read(s2.getId()));
+		assertNotNull(d.read(s3.getId()));
+		assertNotNull(d.read(s4.getId()));
+
+		s1.setName("updated");
+		s2.setName("updated");
+		s3.setName("updated");
+		s4.setName("updated");
+
+		d.updateAll(List.of(s1, s2, s3, s4));
+
+		assertEquals("updated", d.read(s1.getId()).getName());
+		assertEquals("updated", d.read(s2.getId()).getName());
+		assertEquals("updated", d.read(s3.getId()).getName());
+		assertEquals("updated", d.read(s4.getId()).getName());
+
+		d.deleteAll(List.of(s1, s2, s3, s4));
+	}
+
 }