diff --git a/src/config.py b/src/config.py
index df02207a..55140bbb 100755
--- a/src/config.py
+++ b/src/config.py
@@ -1,6 +1,6 @@
 from distutils.util import get_platform
 
-version = '4.5.0'
+version = '4.5.1'
 
 version_info = '''
 Pyarmor is a tool used to import or run the encrypted python scripts.
diff --git a/src/utils.py b/src/utils.py
index a896d4e4..cbc76f73 100755
--- a/src/utils.py
+++ b/src/utils.py
@@ -46,7 +46,7 @@ def search_pytransform(path):
         shutil.copy(src, path)
     else:
         raise RuntimeError('No library %s found' % src)
-if not os.path.exists(dll_name + dll_ext):
+if not os.path.exists(os.path.join(PYARMOR_PATH, dll_name + dll_ext)):
     search_pytransform(PYARMOR_PATH)
 
 import pytransform