diff --git a/cluster_pack/packaging.py b/cluster_pack/packaging.py
index 002a314..67f0409 100644
--- a/cluster_pack/packaging.py
+++ b/cluster_pack/packaging.py
@@ -399,14 +399,19 @@ def detect_archive_names(
             and os.path.isdir(pex_file)
             and not package_path.endswith('.zip')):
 
-        pex_files = glob.glob(f"{os.path.dirname(pex_file)}/*.pex.zip")
-        assert len(pex_files) == 1, \
-            f"Expected to find single zipped PEX in same dir as {pex_file}, got {pex_files}"
-        package_path = _build_package_path(os.path.basename(pex_files[0]), None)
+        zip_pex_file = resolve_zip_from_pex_dir(pex_file)
+        package_path = _build_package_path(os.path.basename(zip_pex_file), None)
 
     return package_path, env_name, pex_file
 
 
+def resolve_zip_from_pex_dir(pex_dir: str) -> str:
+    pex_files = glob.glob(f"{os.path.dirname(pex_dir)}/*.pex.zip")
+    assert len(pex_files) == 1, \
+        f"Expected to find single zipped PEX in same dir as {pex_dir}, got {pex_files}"
+    return pex_files[0]
+
+
 def detect_packer_from_spec(spec_file: str) -> Packer:
     if os.path.basename(spec_file) == "requirements.txt":
         return PEX_PACKER
diff --git a/cluster_pack/uploader.py b/cluster_pack/uploader.py
index 7b73b48..0c06d8c 100644
--- a/cluster_pack/uploader.py
+++ b/cluster_pack/uploader.py
@@ -109,7 +109,7 @@ def upload_zip(
             request.urlretrieve(zip_file, tmp_zip_file)
             zip_file = tmp_zip_file
 
-        _upload_zip(zip_file, package_path, resolved_fs, force_upload)
+        _upload_pex_file(packer, zip_file, package_path, resolved_fs, force_upload)
 
         return package_path
 
@@ -167,7 +167,7 @@ def upload_env(
             additional_indexes=additional_indexes
         )
     else:
-        _upload_zip(pex_file, package_path, resolved_fs, force_upload)
+        _upload_pex_file(packer, pex_file, package_path, resolved_fs, force_upload)
 
     return (package_path,
             env_name)
@@ -244,28 +244,38 @@ def _get_hash(spec_file: str) -> str:
         return hashlib.sha1(f.read().encode()).hexdigest()
 
 
-def _upload_zip(
-        zip_file: str, package_path: str,
+def _upload_pex_file(
+        packer: packaging.Packer,
+        pex_file_or_dir: str, package_path: str,
         resolved_fs: Any = None, force_upload: bool = False
 ) -> None:
-    packer = packaging.detect_packer_from_file(zip_file)
     if packer == packaging.PEX_PACKER and resolved_fs.exists(package_path):
         with tempfile.TemporaryDirectory() as tempdir:
             local_copy_path = os.path.join(tempdir, os.path.basename(package_path))
             resolved_fs.get(package_path, local_copy_path)
             info_from_storage = PexInfo.from_pex(local_copy_path)
-            info_to_upload = PexInfo.from_pex(zip_file)
+            info_to_upload = PexInfo.from_pex(pex_file_or_dir)
             if not force_upload and info_from_storage.code_hash == info_to_upload.code_hash:
-                _logger.info(f"skip upload of current {zip_file}"
+                _logger.info(f"skip upload of current {pex_file_or_dir}"
                              f" as it is already uploaded on {package_path}")
                 return
 
-    _logger.info(f"upload current {zip_file} to {package_path}")
-
     dir = os.path.dirname(package_path)
     if not resolved_fs.exists(dir):
         resolved_fs.mkdir(dir)
-    resolved_fs.put(zip_file, package_path)
+
+    pex_file = (
+        packaging.resolve_zip_from_pex_dir(pex_file_or_dir) if os.path.isdir(pex_file_or_dir)
+        else pex_file_or_dir
+    )
+    _logger.info(f"upload current {pex_file} to {package_path}")
+
+    try:
+        resolved_fs.put(pex_file, package_path)
+    except OSError:
+        if resolved_fs.exists(package_path):
+            resolved_fs.rm(package_path)
+
     # Remove previous metadata
     archive_meta_data = _get_archive_metadata_path(package_path)
     if resolved_fs.exists(archive_meta_data):