If you are an advanced user needing this for a one-off repair, you are likely better off using the built-in BIOS interface to set the Serial Number. If that option is unavailable, you should contact an Acer service center. If you choose to download the tool from a third-party forum, scan it aggressively for viruses and ensure you have a BIOS backup before running it.
Once you have sourced a legitimate DMI Tool executable, follow this process exactly. acer dmi tool link
Acer does not publish a universal DMI tool link. To get the correct file: 👉 Provide your exact model number (e.g., Aspire A315-56, Veriton X4640G) and I can guide you to the right official BIOS package that contains the tool. If you are an advanced user needing this