Tech
08 Sep 2026
7 min read
Why an SD Card Can Become Read-Only
An SD card can behave normally when you open photos or copy files from it, yet refuse to save new files, delete old ones, or format the card. A camera may call the card “locked” or “write-protected,” while a computer may describe it as read-only. These messages all point to the same practical distinction: reading data and changing data are separate operations. A device may still be able to retrieve existing information even when writes are being blocked.