ATATool is freeware software that is used to display and modify ATA disk information from a Microsoft Windows environment.

[1] The software is typically used to manage host protected area (HPA) and device configuration overlay (DCO) features and is broadly similar to the hdparm for Linux.

[2] ATATool is no longer available for personal download and can only be used for "professional users" like for security researchers.

On Windows Vista and later it requires an elevated-privileges command prompt (see User Account Control).

Display detected Hard Drives: Display information on Hard Drive 1: Set a volatile HPA of 50GB on Hard Drive 1 (HPA will be lost after a power cycle): Set a permanent HPA of 50GB on Hard Drive 1 (HPA will still stay after power cycles): Remove permanent HPA on Hard Drive 1: Set DCO to 100GB on Hard Drive 1: Remove DCO of 100GB on Hard Drive 1: Make sector 5 bad: Make sector 5 not bad: Make sector 10 bad and then not bad again (alternative method): Using ATATool can permanently change the disk configuration, may result in permanent data loss by making some sectors of the disk inaccessible.