diff --git a/ddsc/core/filedownloader.py b/ddsc/core/filedownloader.py
index 5049aac..e8ab7f5 100644
--- a/ddsc/core/filedownloader.py
+++ b/ddsc/core/filedownloader.py
@@ -106,8 +106,9 @@ class FileDownloader(object):
         Write out a empty file so the workers can seek to where they should write and write their data.
         """
         with open(self.path, "wb") as outfile:
-            outfile.seek(int(self.file_size) - 1)
-            outfile.write(b'\0')
+            if self.file_size > 0:
+                outfile.seek(int(self.file_size) - 1)
+                outfile.write(b'\0')
 
     def make_and_start_process(self, range_start, range_end, progress_queue):
         """
diff --git a/ddsc/core/fileuploader.py b/ddsc/core/fileuploader.py
index 43356c5..4b57b61 100644
--- a/ddsc/core/fileuploader.py
+++ b/ddsc/core/fileuploader.py
@@ -181,12 +181,14 @@ class ParallelChunkProcessor(object):
             processes.append(self.make_and_start_process(index, num_items, progress_queue))
         wait_for_processes(processes, num_chunks, progress_queue, self.watcher, self.local_file)
 
-
     @staticmethod
     def determine_num_chunks(chunk_size, file_size):
         """
         Figure out how many pieces we are sending the file in.
+        NOTE: duke-data-service requires an empty chunk to be uploaded for empty files.
         """
+        if file_size == 0:
+            return 1
         return int(math.ceil(float(file_size) / float(chunk_size)))
 
     @staticmethod
diff --git a/ddsc/tests/empty_file b/ddsc/tests/empty_file
new file mode 100644
index 0000000..e69de29
diff --git a/setup.py b/setup.py
index 8fee84a..2fe9f5b 100644
--- a/setup.py
+++ b/setup.py
@@ -2,7 +2,7 @@ from setuptools import setup
 
 
 setup(name='DukeDSClient',
-        version='0.2.8',
+        version='0.2.9',
         description='Command line tool(ddsclient) to upload/manage projects on the duke-data-service.',
         url='https://github.com/Duke-GCB/DukeDSClient',
         keywords='duke dds dukedataservice',

“range() step argument must not be zero”
Crash at approx. 30% completion, uploading a folder to a new project: “range() step argument must not be zero”
<img width="806" alt="screen shot 2016-05-25 at 1 31 11 pm" src="https://cloud.githubusercontent.com/assets/11540881/15551266/38d08f16-2283-11e6-9708-c5f93edb99d9.png">

Is there a verbose logging option we can use to determine where, exactly, this is failing?
diff --git a/ddsc/core/tests/test_fileuploader.py b/ddsc/core/tests/test_fileuploader.py
index f8ca72b..44bfb7e 100644
--- a/ddsc/core/tests/test_fileuploader.py
+++ b/ddsc/core/tests/test_fileuploader.py
@@ -47,6 +47,7 @@ class TestParallelChunkProcessor(TestCase):
             (100, 900000, 9000),
             (125, 123, 1),
             (122, 123, 2),
+            (100, 0, 1)
         ]
         for chunk_size, file_size, expected in values:
             num_chunks = ParallelChunkProcessor.determine_num_chunks(chunk_size, file_size)
@@ -63,4 +64,4 @@ class TestParallelChunkProcessor(TestCase):
         ]
         for upload_workers, num_chunks, expected in values:
             result = ParallelChunkProcessor.make_work_parcels(upload_workers, num_chunks)
-            self.assertEqual(expected, result)
\ No newline at end of file
+            self.assertEqual(expected, result)

pip install -e .[dev]
parse_log_pytest
requirements.txt
nose pytest
3.9
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
-e git+https://github.com/Duke-GCB/DukeDSClient.git@81d8fc03fdbb9209d949f319bf4b4691b1615a59#egg=DukeDSClient
exceptiongroup==1.2.2
iniconfig==2.1.0
nose==1.3.7
packaging==24.2
pluggy==1.5.0
pytest==8.3.5
PyYAML==3.11
requests==2.9.1
tomli==2.2.1

name: DukeDSClient
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.4.4=h6a678d5_1
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=3.0.16=h5eee18b_0
  - pip=25.0=py39h06a4308_0
  - python=3.9.21=he870216_1
  - readline=8.2=h5eee18b_0
  - setuptools=75.8.0=py39h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - tzdata=2025a=h04d1e81_0
  - wheel=0.45.1=py39h06a4308_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - exceptiongroup==1.2.2
      - iniconfig==2.1.0
      - nose==1.3.7
      - packaging==24.2
      - pluggy==1.5.0
      - pytest==8.3.5
      - pyyaml==3.11
      - requests==2.9.1
      - tomli==2.2.1
prefix: /opt/conda/envs/DukeDSClient

ddsc/core/tests/test_fileuploader.py::TestParallelChunkProcessor::test_determine_num_chunks
ddsc/core/tests/test_fileuploader.py::TestFileUploader::test_make_chunk_processor_with_none ddsc/core/tests/test_fileuploader.py::TestFileUploader::test_make_chunk_processor_with_one ddsc/core/tests/test_fileuploader.py::TestFileUploader::test_make_chunk_processor_with_two ddsc/core/tests/test_fileuploader.py::TestParallelChunkProcessor::test_make_work_parcels
setup.py ddsc/core/filedownloader.py ddsc/core/fileuploader.py ddsc/tests/empty_file
setup.py ddsc/core/filedownloader.py ddsc/core/fileuploader.py ddsc/tests/empty_file