Drive and all partitions detected in Disk Management, but assigning a drive letter is grayed out

Question

I'm not sure what the problem is. I'm having a lot of hard drive issues all of a sudden. Two of my drives work fine, 1 empty one refuses to initialize, the one in the screenshot won't let me assign a drive letter, and my former external hard drive (removed it from the enclosure, put it in the computer) has seemingly wiped itself somehow (argh).

I'm using Windows 7 Pro x64, and all of these drives are SATA, except for K: which is IDE. It's not a power supply issue, 700w is way more than enough for everything I have in the case.

Answer 1

Use CMD's tool DiskPart for the partitioning and formatting of the drives.

Commands you may then issue at the DISKPART prompt:

LIST   Disk
LIST   Partition
LIST   Volume

SELECT Disk=n
SELECT Partition=n
SELECT Volume=n_or_d  (Number or Drive Letter)

DETAIL Disk
DETAIL Partition
DETAIL volume

ACTIVE  (set the current in-focus partition to be the system partition)
ASSIGN  (allocate the next free drive letter)
ASSIGN LETTER=E   (Choose a free letter)
ATTRIBUTES DISK [{set | clear}] [readonly] [noerr]
ATTRIBUTES VOLUME [{set | clear}] [{hidden | readonly | nodefaultdriveletter | shadowcopy}] [noerr]
AUTOMOUNT [enable] [disable] [scrub] [noerr]
FILESYSTEMS     (Use 'Select Volume' first)
HELP
INACTIVE   (mark a system/boot partition as inactive [don’t boot], use 'Select Partition' first)
OFFLINE disk [noerr] (Take the current disc offline, use 'Select Disk' first)
ONLINE {disk|volume} [noerr]
REM  (remark/comment)
REMOVE letter=E [dismount] [noerr]  (Remove drive letter E from the in-focus partition)
REMOVE mount=path [dismount] [noerr]  (Remove mount point from the in-focus partition)
REMOVE /ALL [dismount] [noerr]    (Remove ALL current drive letters and mount points)
RESCAN     (Locate new disks that have been added to the computer)
SHRINK [desired=n] [minimum=n] [nowait] [noerr]  (Reduce the size of the in-focus volume)
SHRINK querymax [noerr]
EXIT
UNIQUEID disk [id={dword | GUID}] [noerr]   (Display or set the GUID partition table identifier or MBR signature for the disk with focus)

Commands to Manage Basic Disks:

ASSIGN MOUNT=path  (Choose a mount point path for the volume)
CREATE PARTITION Primary Size=50000  (50 GB)
CREATE PARTITION Extended Size=25000
CREATE PARTITION logical Size=25000
DELETE Partition
EXTEND Size=10000
GPT attributes=n   (assign GUID Partition Table attributes)
SET id=byte|GUID [override] [noerr]   (Change the partition type)

Commands to Manage Dynamic Disks:

ADD disk=n   (Add a mirror to the in-focus SIMPLE volume on the specified disk see 'Diskpart Help' for more.)
BREAK disk=n  (Break the current in-focus mirror)
CREATE VOLUME Simple Size=n Disk=n
CREATE VOLUME Stripe Size=n Disk=n,n,...
CREATE VOLUME Raid Size=n Disk=n,n,...
DELETE DISK
DELETE PARTITION
DELETE VOLUME
EXTEND Disk=n [Size=n]
EXTEND Filesystem [noerr]
IMPORT [noerr]   (Import a foreign disk group, use 'Select Disc' first)
RECOVER [noerr]  (Refresh disc pack state, attempt recovery on an invalid pack, & resynchronize stale plex/parity data.)
REPAIR disk=n [align=n] [noerr]  (Repair the RAID-5 volume with focus, replace with the specified dynamic disk)
RETAIN   (Prepare an existing dynamic simple volume to be used as a boot or system volume)

Commands to Convert Disks:

CONVERT basic
CONVERT dynamic
CONVERT gpt
CONVERT mbr
CLEAN [ALL]   (remove all partition and volume info from the hard drive)
FORMAT [{fs=ntfs|fat|fat32] [revision=x.xx] | recommended}] [label="label"] [unit=n] [quick] [compress] [override] [nowait] [noerr]

The diskpart commands may be placed in a text file (one command per line) and used as an input file to diskpart.exe:

DiskPart.exe < myscript.txt

Example:

SELECT DISK=0
CREATE PARTITION PRIMARY
ASSIGN LETTER=E
SELECT PARTITION=1
FORMAT FS=NTFS LABEL="New Volume" QUICK
EXIT 

noerr - This option is for scripting only. With noerr set, when an error is encountered, DiskPart will continue to process commands as if the error did not occur. Without this parameter, an error causes DiskPart to exit with an error code.

When selecting a volume or partition, you may use either the number or drive letter or the mount point path.

For Microsoft support: http://support.microsoft.com/kb/300415

Answer 2

There are 6 partitions on that hard drive, while you can have max 4 to keep it working. Windows prevents any modifications because it has detected unrecognized partition configuration.

I have no idea what piece of software allowed you to create those. I guess it can be a corrupted partition table (that 1 MB and 10 MB partitions look suspicious, did you create those?)

Anyway, last time I saw something like that, I was able to remove excessive partitions with TestDisk. Dropping the first two partitions (these suspicious ones) will reduce number to 4 primary ones, allowing you to rescue your data on Windows. Then you should repartition the drive to be sure it won't fail when you least expect it.

If you need more than 4 partitions, create three primary ones and fourth extended partition. Then you'll be able to create logical disks inside it.

Answer 3

You moved disk 1 form an external enclosure (USB I'm guessing) to inside the machine.
This usually works without a hitch, but...
Some enclosures contain a USB-2-SATA chip that represents the disk with a different geometry (heads, tracks, sectors or LBA mode) than what the drive really uses internally.

That seems to be the case here:
When the drive is directly mounted in the computer Windows sees the real geometry and considers the partition table corrupt because it was written on basis of the geometry as supplied by the enclosure.
Windows threats a "corrupt" partitontable the same was as an un-initialized disk.
Don't initialize it !!!!
If you do, you loose all content. Just put it back into the enclosure you should be able to get at your data, as long as you don't initialize it.

Furthermore: Because Windows has retained some information about the partitions on the disk when it was still external the disk-administrator may get very confused.
It does realize that this is the same disk, but the low-level device driver thinks it corrupt because of the different geometry, while the filesystems appear there (cached form the previous use).

This will remain a problem: In my experience the only way to get Windows to properly recognize the disk when it is used internally is to initialize it fresh. So you will have to rescue your data first.
After re-initialize, and a reboot of the computer, disk-administrator should be back to normal.

Answer 4

Go into command prompt. 1) type in diskpart 2) type disk list to see the list of disks 3) select which one you want, and type in select disk (the number the disk you want is) 4) then (I think) type clear. This will set up the hard drive as unallocated space 5) go to disk Management and select the drive you want to change. Right click and select initialize. 6) go through all the steps and your done

Check YouTube sources along the lines of this tutorial. It worked for me and it might for you.