How to completely erase Seagate external backup secure drive

Solution 1:

Which kind of erasure security do you need ? If you need "only" the status: No recovery by (extended) keyboard and software attacks and without destruction of the SSD (CLEAR state), then a full format (Windows Vista and higher) is enough. But if you need the status: No recovery by laboratory and destructive attacks (PURGE state): No chance, you have to destroy the SSD. -> In theory there will be the possibility to do a PURGE by firmware commands, but as you have written, that SeaTools failed, it will not be possible. there is a limitation in the firmware and / or the integrated USB2SATA adapter to successful apply the proper commands. In practice to use other commands or programs makes no sense and you will not get the 100% guarantee that all data are gone.