Hi Mohit,
For us to narrow it down and provide you the proper resolution, may we know if you are trying to delete a Windows registry or a Software registry from a certain application.
Registry disclaimer
Important: This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection,
back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, refer to the following Microsoft Knowledge Base article.
How to back up and restore the registry in Windows
Should you need further assistance, feel free to get back to us.
Regards.