Support Can I change the ext3 to ext4 without formatting my HDD? Applied Models: All NAS Series Answer: No, you need to format the HDD then select the ext4 format. Release date: 2013-04-19 Was it helpful? Yes. No. Thank you for your feedback. Thank you for your feedback. If you have any question, please contact firstname.lastname@example.org 25% of people think it helps.