diff --git a/Minio/ApiEndpoints/BucketOperations.cs b/Minio/ApiEndpoints/BucketOperations.cs
index 12f6e6ff5..89df417ed 100644
--- a/Minio/ApiEndpoints/BucketOperations.cs
+++ b/Minio/ApiEndpoints/BucketOperations.cs
@@ -72,7 +72,7 @@ public async Task MakeBucketAsync(string bucketName, string location = "us-east-
                     location = this.Region;
                 }
             }
-          
+
             // Set Target URL
             Uri requestUrl = RequestUtil.MakeTargetURL(this.BaseUrl, this.Secure,location);
             SetTargetURL(requestUrl);
@@ -134,20 +134,27 @@ public async Task RemoveBucketAsync(string bucketName, CancellationToken cancell
         /// List all objects non-recursively in a bucket with a given prefix, optionally emulating a directory
         /// </summary>
         /// <param name="bucketName">Bucket to list objects from</param>
-        /// <param name="prefix">Filters all objects not beginning with a given prefix</param>
-        /// <param name="recursive">Set to false to emulate a directory</param>
+        /// <param name="prefix">Filters all objects beginning with a given prefix</param>
+        /// <param name="recursive">Set to true to recursively list all objects</param>
         /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
         /// <returns>An observable of items that client can subscribe to</returns>
-        public IObservable<Item> ListObjectsAsync(string bucketName, string prefix = null, bool recursive = true, CancellationToken cancellationToken = default(CancellationToken))
+        public IObservable<Item> ListObjectsAsync(string bucketName, string prefix = "", bool recursive = false, CancellationToken cancellationToken = default(CancellationToken))
         {
             return Observable.Create<Item>(
               async obs =>
               {
                   bool isRunning = true;
                   string marker = null;
+
+                  var delimiter = "/"
+                  if (recursive)
+                  {
+                      delimiter = ""
+                  }
+
                   while (isRunning)
                   {
-                      Tuple<ListBucketResult, List<Item>> result = await GetObjectListAsync(bucketName, prefix, recursive, marker, cancellationToken).ConfigureAwait(false);
+                      Tuple<ListBucketResult, List<Item>> result = await GetObjectListAsync(bucketName, prefix, delimiter, marker, cancellationToken).ConfigureAwait(false);
                       Item lastItem = null;
                       foreach (Item item in result.Item2)
                       {
@@ -171,35 +178,30 @@ public IObservable<Item> ListObjectsAsync(string bucketName, string prefix = nul
         /// Gets the list of objects in the bucket filtered by prefix
         /// </summary>
         /// <param name="bucketName">Bucket to list objects from</param>
-        /// <param name="prefix">Filters all objects not beginning with a given prefix</param>
-        /// <param name="recursive">Set to false to emulate a directory</param>
+        /// <param name="prefix">Filters all objects starting with a given prefix</param>
+        /// <param name="delimiter">Delimit the output upto this character</param>
         /// <param name="marker">marks location in the iterator sequence</param>
         /// <returns>Task with a tuple populated with objects</returns>
         /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
 
-        private async Task<Tuple<ListBucketResult, List<Item>>> GetObjectListAsync(string bucketName, string prefix, bool recursive, string marker, CancellationToken cancellationToken = default(CancellationToken))
+        private async Task<Tuple<ListBucketResult, List<Item>>> GetObjectListAsync(string bucketName, string prefix, string delimiter, string marker, CancellationToken cancellationToken = default(CancellationToken))
         {
             var queries = new List<string>();
-            if (!recursive)
-            {
-                queries.Add("delimiter=%2F");
-            }
-            if (prefix != null)
-            {
-                queries.Add("prefix=" + Uri.EscapeDataString(prefix));
-            }
+            queries.Add("delimiter="+ Uri.EscapeDataString(delimiter));
+            queries.Add("prefix=" + Uri.EscapeDataString(prefix));
+            queries.Add("max-keys=1000");
+
             if (marker != null)
             {
                 queries.Add("marker=" + Uri.EscapeDataString(marker));
             }
-            queries.Add("max-keys=1000");
             string query = string.Join("&", queries);
 
             var request = await this.CreateRequest(Method.GET,
                                                      bucketName,
                                                      resourcePath: "?" + query)
                                         .ConfigureAwait(false);
-            
+
             var response = await this.ExecuteTaskAsync(this.NoErrorHandlers, request, cancellationToken).ConfigureAwait(false);
 
             var contentBytes = System.Text.Encoding.UTF8.GetBytes(response.Content);
@@ -292,7 +294,7 @@ public async Task<BucketNotification> GetBucketNotificationsAsync(string bucketN
                                                resourcePath: "?notification")
                                     .ConfigureAwait(false);
             BucketNotification notification = null;
-           
+
             var response = await this.ExecuteTaskAsync(this.NoErrorHandlers, request, cancellationToken).ConfigureAwait(false);
             var contentBytes = System.Text.Encoding.UTF8.GetBytes(response.Content);
             using (var stream = new MemoryStream(contentBytes))
@@ -314,11 +316,11 @@ public async Task SetBucketNotificationsAsync(string bucketName, BucketNotificat
             var request = await this.CreateRequest(Method.PUT, bucketName,
                                            resourcePath: "?notification")
                                 .ConfigureAwait(false);
-    
+
             request.XmlSerializer = new RestSharp.Serializers.DotNetXmlSerializer();
             request.RequestFormat = DataFormat.Xml;
             request.AddBody(notification);
-            
+
             IRestResponse response = await this.ExecuteTaskAsync(this.NoErrorHandlers, request, cancellationToken).ConfigureAwait(false);
         }
 
@@ -335,4 +337,4 @@ public Task RemoveAllBucketNotificationsAsync(string bucketName, CancellationTok
             return SetBucketNotificationsAsync(bucketName, notification, cancellationToken);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Minio/ApiEndpoints/IBucketOperations.cs b/Minio/ApiEndpoints/IBucketOperations.cs
index 33c8cfacc..a50a5d942 100644
--- a/Minio/ApiEndpoints/IBucketOperations.cs
+++ b/Minio/ApiEndpoints/IBucketOperations.cs
@@ -58,11 +58,11 @@ public interface IBucketOperations
         /// List all objects non-recursively in a bucket with a given prefix, optionally emulating a directory
         /// </summary>
         /// <param name="bucketName">Bucket to list objects from</param>
-        /// <param name="prefix">Filters all objects not beginning with a given prefix</param>
-        /// <param name="recursive">Set to false to emulate a directory</param>
+        /// <param name="prefix">Filter all incomplete uploads starting with this prefix</param>
+        /// <param name="recursive">List incomplete uploads recursively</param>
         /// <param name="cancellationToken"></param>
         /// <returns>An observable of items that client can subscribe to</returns>
-        IObservable<Item> ListObjectsAsync(string bucketName, string prefix = null, bool recursive = true, CancellationToken cancellationToken = default(CancellationToken));
+        IObservable<Item> ListObjectsAsync(string bucketName, string prefix = "", bool recursive = false, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
         /// Get bucket policy
@@ -80,7 +80,7 @@ public interface IBucketOperations
         /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
         /// <returns> Returns Task that sets the current bucket policy</returns>
         Task SetPolicyAsync(String bucketName, String policyJson, CancellationToken cancellationToken = default(CancellationToken));
-       
+
         /// <summary>
         ///  Gets the notification configuration set for this bucket
         /// </summary>
@@ -105,8 +105,8 @@ public interface IBucketOperations
         /// <param name="cancellationToken">optional cancellation token</param>
         /// <returns></returns>
         Task RemoveAllBucketNotificationsAsync(string bucketName, CancellationToken cancellationToken = default(CancellationToken));
-      
+
         // Task ListenBucketNotificationsAsync(string bucketName, string prefix = "", string suffix = "", List<Notification> events,CancellationToken cancellationToken = default(CancellationToken));
-        
+
     }
-}
\ No newline at end of file
+}
diff --git a/Minio/ApiEndpoints/IObjectOperations.cs b/Minio/ApiEndpoints/IObjectOperations.cs
index 8f98be1da..423af234f 100644
--- a/Minio/ApiEndpoints/IObjectOperations.cs
+++ b/Minio/ApiEndpoints/IObjectOperations.cs
@@ -94,10 +94,10 @@ public interface IObjectOperations
         /// </summary>
         /// <param name="bucketName">Bucket to list all incomplepte uploads from</param>
         /// <param name="prefix">prefix to list all incomplete uploads</param>
-        /// <param name="recursive">option to list incomplete uploads recursively</param>
+        /// <param name="recursive">Set to true to recursively list all incomplete uploads</param>
         /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
         /// <returns>A lazily populated list of incomplete uploads</returns>
-        IObservable<Upload> ListIncompleteUploads(string bucketName, string prefix, bool recursive, CancellationToken cancellationToken = default(CancellationToken));
+        IObservable<Upload> ListIncompleteUploads(string bucketName, string prefix = "", bool recursive = false, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
         /// Remove incomplete uploads from a given bucket and objectName
@@ -151,7 +151,7 @@ public interface IObjectOperations
         Task GetObjectAsync(string bucketName, string objectName, string filePath, ServerSideEncryption sse = null ,CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
-        /// Presigned get url - returns a presigned url to access an object's data without credentials.URL can have a maximum expiry of 
+        /// Presigned get url - returns a presigned url to access an object's data without credentials.URL can have a maximum expiry of
         /// upto 7 days or a minimum of 1 second.Additionally, you can override a set of response headers using reqParams.
         /// </summary>
         /// <param name="bucketName">Bucket to retrieve object from</param>
@@ -161,7 +161,7 @@ public interface IObjectOperations
         Task<string> PresignedGetObjectAsync(string bucketName, string objectName, int expiresInt, Dictionary<string,string> reqParams = null);
 
         /// <summary>
-        /// Presigned Put url - returns a presigned url to upload an object without credentials.URL can have a maximum expiry of 
+        /// Presigned Put url - returns a presigned url to upload an object without credentials.URL can have a maximum expiry of
         /// upto 7 days or a minimum of 1 second.
         /// </summary>
         /// <param name="bucketName">Bucket to retrieve object from</param>
@@ -176,4 +176,4 @@ public interface IObjectOperations
         Task<Tuple<string, Dictionary<string, string>>> PresignedPostPolicyAsync(PostPolicy policy);
 
     }
-}
\ No newline at end of file
+}
diff --git a/Minio/ApiEndpoints/ObjectOperations.cs b/Minio/ApiEndpoints/ObjectOperations.cs
index 624b3b540..c84901bd9 100644
--- a/Minio/ApiEndpoints/ObjectOperations.cs
+++ b/Minio/ApiEndpoints/ObjectOperations.cs
@@ -523,10 +523,10 @@ private async Task<string> PutObjectAsync(string bucketName, string objectName,
         {
             var queries = new List<string>();
             queries.Add("uploads");
-            if (prefix != null)
-            {
-                queries.Add("prefix=" + Uri.EscapeDataString(prefix));
-            }
+            queries.Add("prefix=" + Uri.EscapeDataString(prefix));
+            queries.Add("delimiter=" + Uri.EscapeDataString(delimiter));
+            queries.Add("max-uploads=1000");
+
             if (keyMarker != null)
             {
                 queries.Add("key-marker=" + Uri.EscapeDataString(keyMarker));
@@ -535,12 +535,6 @@ private async Task<string> PutObjectAsync(string bucketName, string objectName,
             {
                 queries.Add("upload-id-marker=" + uploadIdMarker);
             }
-            if (delimiter != null)
-            {
-                queries.Add("delimiter=" + delimiter);
-            }
-
-            queries.Add("max-uploads=1000");
 
             string query = string.Join("&", queries);
 
@@ -571,15 +565,15 @@ private async Task<string> PutObjectAsync(string bucketName, string objectName,
         /// Lists all incomplete uploads in a given bucket and prefix recursively
         /// </summary>
         /// <param name="bucketName">Bucket to list all incomplepte uploads from</param>
-        /// <param name="prefix">prefix to list all incomplete uploads</param>
-        /// <param name="recursive">option to list incomplete uploads recursively</param>
+        /// <param name="prefix">Filter all incomplete uploads starting with this prefix</param>
+        /// <param name="recursive">Set to true to recursively list all incomplete uploads</param>
         /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
         /// <returns>A lazily populated list of incomplete uploads</returns>
         public IObservable<Upload> ListIncompleteUploads(string bucketName, string prefix = "", bool recursive = true, CancellationToken cancellationToken = default(CancellationToken))
         {
             if (recursive)
             {
-                return this.listIncompleteUploads(bucketName, prefix, null, cancellationToken);
+                return this.listIncompleteUploads(bucketName, prefix, "", cancellationToken);
             }
             return this.listIncompleteUploads(bucketName, prefix, "/", cancellationToken);
         }
@@ -617,36 +611,6 @@ private IObservable<Upload> listIncompleteUploads(string bucketName, string pref
 
         }
 
-        /// <summary>
-        /// Find uploadId of most recent unsuccessful attempt to upload object to bucket.
-        /// </summary>
-        /// <param name="bucketName"></param>
-        /// <param name="objectName"></param>
-        /// <param name="cancellationToken">Optional cancellation token to cancel the operation</param>
-        /// <returns></returns>
-        private async Task<string> getLatestIncompleteUploadIdAsync(string bucketName, string objectName, CancellationToken cancellationToken)
-        {
-            Upload latestUpload = null;
-            var uploads = await this.ListIncompleteUploads(bucketName, objectName, cancellationToken: cancellationToken).ToArray();
-
-            foreach (Upload upload in uploads)
-            {
-                if (objectName == upload.Key && (latestUpload == null || latestUpload.Initiated.CompareTo(upload.Initiated) < 0))
-                {
-                    latestUpload = upload;
-
-                }
-            }
-            if (latestUpload != null)
-            {
-                return latestUpload.UploadId;
-            }
-            else
-            {
-                return null;
-            }
-
-        }
         /// <summary>
         /// Remove incomplete uploads from a given bucket and objectName
         /// </summary>