When deleting a Form associated to a list with a custom-created content type, the following error might occur: The system cannot find the file specified
- Use SharePoint Manager 2013 which can be downloaded here: https://spm.codeplex.com
- Browse to the list which is having the issue.
- Select the content type which need to be cleaned up.
- Empty the values for the following properties:
- Save the changes and verify if the issue is resolved.