A drive with all my data is showing as unformatted – what do I do?

Occasionally, when moving a drive to another machine, it'll show up as unformatted. I'll look at some possible causes and actions to take.

I recently replaced my system hard drive and have taken my old internal hard drive out and installed it into a external enclosure.

When I plug it in, it shows up on my computer, but without a file system label, only a letter designation (G). Disk management says it is unformatted. It was NTFS as an internal drive. I’m concerned that if I format it, I will lose all of my data now stored on the drive. What steps do I take to format this external drive without losing my files? Or am I missing a step in accessing the information on the drive?

First, don’t format the drive.

Formatting will erase whatever’s on there or, at a minimum, make it more difficult to recover your data.

I do have some suggestions of next steps to take instead.

Unformatted?

When the system indicates that a drive is unformatted, it’s the result of attempting to read the master boot record, partition table, or other partition overhead information on the drive and getting something other than the expected data back.

In most cases, this is the result of the data on the disk somehow having been overwritten or otherwise damaged.

Less commonly, it can also be the result of a hardware failure, either in the disk itself or the circuitry connecting that disk to your computer.
Hardware problems are easiest to rule out.

Try another machine:-

If you have another computer available, plug the external drive into that and see if it is properly recognized.
If it is, then:

• You have access to your data (back it up!).
• You know that there’s an issue with your computer that needs to be addressed.

Verify that external enclosure

Because you indicated that you placed your formerly internal drive into an external enclosure, I’m actually very suspicious that there’s a problem with the assembly.
A working USB interface improperly connected to a hard drive could appear as an unformatted drive.

I’d make absolutely certain that the drive was properly connected to the interface card that’s in that external enclosure. Double (even triple) check that all of the assembly instructions were followed and that the drive is attached the right way.

If you have another known-working hard disk, I’d be really tempted to place that in the enclosure and try it. If it works, then you know that you have a problem with the actual hard disk (which we’ll look into next). If it fails, then you know that there’s either a problem with the enclosure itself, its circuitry, or the connection to your PC.

Data Recovery

If everything seems to be connected and working properly, yet your drive still shows as “unformatted”, it’s time to haul out data recovery software.

Piriform (the company that makes CCleaner) also puts out a free tool called Recuva. Among the other features that they list, they state, “Even if you’ve formatted a drive so that it looks blank, Recuva can still find your files on it.”

Naturally, no one can guarantee complete recovery, but it’s a place to start.
Another tool to consider is GetDataBack. It’s not free, but the free demo version should allow you to determine if the utility will be able to recover anything. If so, the tool might be well worth it. From their feature list: “GetDataBack will recover your data if the hard drive’s partition table, boot record, FAT/MFT or root directory are lost or damaged …”

This would have been moot if…

I’d be remiss in my job if I didn’t point out that none of this would matter or at least it wouldn’t matter nearly as much, if you’d had a backup of the contents of that drive.

Remember the rule of thumb: if it’s only in one place it’s not backed up.
Hard drives do fail and often without warning. That can result in complete data loss.

Whether or not you recover your data this time, resolve to put a backup strategy into place so that the next time that there’s an issue (and please trust me, there will be a next time) the solution is simple to get the most recent backup.