diff --git a/arc/common.py b/arc/common.py
index b85b676274..924ba45722 100644
--- a/arc/common.py
+++ b/arc/common.py
@@ -1705,3 +1705,16 @@ def is_xyz_mol_match(mol: 'Molecule',
         if element not in element_dict_xyz or element_dict_xyz[element] != count:
            return False
     return True
+
+
+def fill_in_the_blanks(folder_name: str):
+    """
+    Adding backslashes before spaces in the folder name.
+
+    Args:
+        folder_name (str): The string directory we want to modify.
+
+    Returns:
+        str: Modified folder name.
+    """
+    return folder_name.replace(" ", "\ ")
diff --git a/arc/common_test.py b/arc/common_test.py
index 10f746bb41..3dc9204495 100644
--- a/arc/common_test.py
+++ b/arc/common_test.py
@@ -1370,6 +1370,17 @@ def test_is_xyz_mol_match(self):
         self.assertFalse(common.is_xyz_mol_match(mol1, xyz2))
         self.assertTrue(common.is_xyz_mol_match(mol2, xyz2))
 
+    def test_fill_in_the_blanks(self):
+        """Test the fill_in_the_blanks() function"""
+        ex1 = "michalkfir"
+        ex2 = "michal kfir"
+        ex3 = "mich al kfir"
+        ex4 = "michal  kfir"
+        self.assertEqual(common.fill_in_the_blanks(ex1), "michalkfir")
+        self.assertEqual(common.fill_in_the_blanks(ex2), "michal\\ kfir")
+        self.assertEqual(common.fill_in_the_blanks(ex3), "mich\\ al\\ kfir")
+        self.assertEqual(common.fill_in_the_blanks(ex4), "michal\\ \\ kfir")
+
     @classmethod
     def tearDownClass(cls):
         """
diff --git a/arc/main.py b/arc/main.py
index 9df94e0738..8016d65081 100644
--- a/arc/main.py
+++ b/arc/main.py
@@ -27,6 +27,7 @@
                         ARC_PATH,
                         check_ess_settings,
                         delete_check_files,
+                        fill_in_the_blanks,
                         get_logger,
                         globalize_path,
                         initialize_job_types,
@@ -280,6 +281,7 @@ def __init__(self,
         self.verbose = verbose
         self.project_directory = project_directory if project_directory is not None \
             else os.path.join(ARC_PATH, 'Projects', self.project)
+        self.project_directory = fill_in_the_blanks(self.project_directory)
         if not os.path.exists(self.project_directory):
             os.makedirs(self.project_directory)
         self.output = output