diff --git a/lib/spack/spack/fetch_strategy.py b/lib/spack/spack/fetch_strategy.py
index 4349e32d4f..21802c4556 100644
--- a/lib/spack/spack/fetch_strategy.py
+++ b/lib/spack/spack/fetch_strategy.py
@@ -306,7 +306,7 @@ def archive(self, destination):
         if not self.archive_file:
             raise NoArchiveFileError("Cannot call archive() before fetching.")
 
-        shutil.copy(self.archive_file, destination)
+        shutil.copyfile(self.archive_file, destination)
 
     @_needs_stage
     def check(self):