Sets whether VSS stores change information between versions of a file. The default is Yes.
Store_Deltas = {Yes|No}
Stores all changes between file versions:
Store_Deltas = Yes
You should use this variable rarely. Setting this variable to No saves disk space on the VSS server, but doesn't allow you to re-create past versions of files.
When you add files to VSS, the Add Files command lets you decide if VSS retains its old version of a file or only the latest version by using the Store Only Latest Version check box in the Advanced options in the Add Files dialog box. Setting the Store_Deltas variable controls the default setting of this option. The default is Yes, but you can manually override this setting for individual files in the Add Files dialog box.