diff --git a/share/gitian-updater b/share/gitian-updater
index f708493..8894572 100755
--- a/share/gitian-updater
+++ b/share/gitian-updater
@@ -353,15 +353,15 @@ if quiet == 0:
 for root, dirs, files in os.walk(unpack_dir, topdown = True):
     rel = path.relpath(root, unpack_dir)
     if not path.exists(path.join(dest_path, rel)):
-        os.mkdir(path.join(dest_path, rel))
+        os.mkdir(path.normpath(path.join(dest_path, rel)))
     for f in files:
         shutil.copy2(path.join(root, f), path.join(dest_path, rel, f))
 
-removed = set(old_manifest['sums'].keys()).difference(out_manifest['sums'].keys())
-
-for f in removed:
-    if path.exists(path.join(dest_path, f)):
-        os.unlink(path.join(dest_path, f))
+if old_manifest:
+    removed = set(old_manifest['sums'].keys()).difference(out_manifest['sums'].keys())
+    for f in removed:
+        if path.exists(path.join(dest_path, f)):
+            os.unlink(path.join(dest_path, f))
 
 f = file(path.join(dest_path, '.gitian-manifest'), 'w')
 yaml.dump(out_manifest, f)