diff --git a/tools/oneclick/base/hdl_config.py b/tools/oneclick/base/hdl_config.py
index 191cf57909c6b5837c9a71ff816641db6945ccd5..fb3c3bffbde6bbada6206e58a21e554ad36843bb 100644
--- a/tools/oneclick/base/hdl_config.py
+++ b/tools/oneclick/base/hdl_config.py
@@ -115,10 +115,10 @@ class HdlConfig:
                 self.libs.remove_dict_from_list(ld)
                 
         # Keep list of removed HDL library names of found, but removed technology dicts
-        self.removed_lib_names = self.libs.get_key_values('hdl_lib_name', self.removed_dicts)
+        self.removed_lib_names = self.libs.get_key_values(key='hdl_lib_name', dicts=self.removed_dicts, must_exist=True)
         
         # Keep list of used HDL library names
-        self.lib_names = self.libs.get_key_values('hdl_lib_name')
+        self.lib_names = self.libs.get_key_values(key='hdl_lib_name', must_exist=True)
         
         # Check that there are no duplicate library names (eg. due to copying a hdlib.cfg without modifying the hdl_lib_name value)
         duplicate_lib_names = cm.list_duplicates(self.lib_names)