What is read/write accessibility?

The Drive Settings window includes information about the Drive Security attributes. "Read/Write Accessible" is one of the attributes that displays if a drive's data has been locked.

To view Drive Security attributes, go to the Hardware page. Select a drive, click View settings, and then click Show more settings. At the bottom of the page, the Read/Write Accessible attribute value is Yes when the drive is unlocked. The Read/Write Accessible attribute value is No, invalid security key when the drive is locked. You can unlock a secure drive by importing a security key (go to Settings > System > Unlock Secure Drives).