Setting NTFS rights to deny Delete permission

This can be done by editing the advanced security properties of the folder and files. To do this, right click on the folder in question and select "Properties." Select the Security tab and click "Advanced." Add or edit the appropriate users and specify the following permissions:

          Traverse Folder/Execute Data
           List Folder/Read Data
           Read Attributes
           Read Extended Attributes
           Create Files/Write Data
           Create Folders/Append Data
           Write Attributes
           Write Extended Attributes
           Read Permissions
           Change Permissions

You may or may not need all of the above permissions for your specific requirements. The key is to remember to NOT grant the "Delete Subfolders and Files" and "Delete" permissions.

Keep in mind that you may need to remove inheritance to allow you to make the necessary changes.