This error occurs when saving edits to a theme or table:
"Error calling unlink for file <home>\delta1.rcm"
where, 'home' represents the path to the folder currently defined as ArcView's HOME directory.
When you edit a shapefile, a number of temporary delta files are created in the
HOME directory. These files are of the type .rcm or Record Map. ArcView will
produce an error message when it has problems creating or reading any of
these files; that often occurs when the hard disk has become full.
Clean up the disk containing HOME, or change HOME to a different disk.