WorkbookConnection.Delete Method (Excel)
Deletes a workbook connection.
Use this method to delete an external data connection. This method does not apply to links to other workbooks.
Deleting a connection will not delete or remove any objects that were using that connection. Deleting a connection will not cause any of the connection files to be deleted from the file system. If you edit any of those objects to use another connection, everything will start working again.
Objects that use a deleted connection behave as if the connection could not be established.