For Intel-based Acer tablets (like the Iconia W series), the process is more complex. Acer often locked the bootloader, and the Intel Phone Flash Tool requires a specific "bootloader unlock code" from Acer—which is no longer available for legacy devices.

This is the most common scenario. The process varies for Intel, but the principles remain.

Download the specific "Stock ROM" or "Scatter File" for the specific Acer model from Acer's official support archives or reputable third-party databases (e.g., needrom, xda-developers).