Sometimes in the Windows Event Log you may see an error or warning about disk problems regarding something like:
\Device\Harddisk0\D.
Presumably, the Harddisk0 refers to the first physical drive as reported by the Disk Management MMC snap-in (though I have personally never seen anything other than disk 0 being reported even with different drives and even when the drive in question was definitely a different one—like the SD card in the card-reader).
But what is the D?
It definitely isn’t a partition. Physical problems affect the whole drive, not a single volume, plus the System\Disk event log entries logs physical problems; filesystem issues are logged to Application\Winlogon.
So what does the D refer to? Has anyone ever seen a different letter? Googling for \Device\Harddisk0\C returns a small handful of results which are most likely just a typos. I managed to find one person who asked this question but got no answer.


\Device\Harddisk0\DR0? Maybe the code reporting the error had a bug and chopped off the last two letters... – user541686 May 27 '13 at 19:33\D, this weekend with the SD card, last year with an old Maxtor, every time I’ve ever seen that warning, it’s alwaysHarddisk0\D(even the number never varies). – Synetech May 27 '13 at 20:13