Creo™ Schematics 4.0 Help Center > Design Basics > Working with an Internal Catalog > Internal Catalog Parameters > The Name Parameter > To Reset Serial Numbers in Automatically Generated Names
  
To Reset Serial Numbers in Automatically Generated Names
The serial number used in an automatically generated name is always greater than the last one used. Numbers are not automatically reused even if they are available.
Serial numbers can be manually or automatically reset. To automatically reset a serial number, click Design > Design Properties > Reset Serial Numbers, and then click OK. The new instances on the design sheet are given new serial numbers. Existing serial numbers are not changed and may have to be manually reset.