Unallocated drive, partition recovered but not recognized

Yes, why PW is refusing to assign a drive letter and make it visible in Windows is still a mystery.

When you have finished copying the partition to another drive and satisfied that you have all data and breath easy :), we shall try and see whether that 3TB external drive can be recovered as it is.

You would initialise the drive after backing up some important sectors with Bootice .

The common and mistaken perception is that initialisation will destroy all data. I very often see even learned Gurus saying " No, No do not initialise. You will be doomed and lose all your data"

Wrong. Initialisation only prepares the drive and makes it visible to Windows Disk Management, ready for creating volumes and then formatting. - that is your drive from being "Unknown" and "Unallocated" will be brought "online" but still "Unallocated"(in the case of a fully wiped out drive being initialised as a GPT drive.) It does not write anything to Sector 264192 or thereafter where the first partition begins and data exists (if already existing)

In the case of a GPT drive initialising writes the Protective MBR to LBA (sector) 0, GPT Header to LBA 1,and part of the Partition table,the 128MB MSR, to LBA2 and nothing more.

(The first volume when created will be at LBA 264192 - you can see it in the PRW screenshot in your first post. (34 is the start of 128MB MSR))

The following screenshot is my 750GB external HDD initialised as GPT - just initialised, I haven't created any volume yet.



So let us know when you have backed up all data in the drive and then we shall backup the relevant sectors as it exists now - just for safety so that we can restore back should we need it - and then let Windows to initialise the drive.

I have to runout now.

Is the partition still visiable in PW if you DON'T scan for it?

When you download Bootice you may have to download the 64bit version or 32bit version according your Windows 7 OS.

More programs by iPauly - Softpedia ( I used to download it directly from iPauly's site but now its all in Chinese .)

Saving with Bootice: Lost partitions!

Save the sectors shown when you click on the Partition button. Give an identifiable name to each saved sector.

There is absolutely no hurry. Do it leisurely. ( I am also a little busy this and next week and may disappear from here frequently, peeping in once in a while.)

Before I run out again, I wanted to post this. So I booted again and hurriedly typing this: If you proceed with asking Windows Disk Management to initialise as GPT, stop with initialisation. Do not proceed further to create a New Simple Volume, assign a drive letter and format it.If need be, we shall do it later.

Before I retire for the day I shall leave further steps to be processed.

In case mere initialisation, does not bring back your 3TB external drive alive:

1. In Windows Disk Management , select your 3TB external drive's unallocated/unformatted/Raw portion, create a New simple volume for the full extent of that space and proceed to give it a drive letter.In the next screen you will be asked to format.Select no format option and finish.

(In case the initialisation process rewrites the partition table for only the 128MB MSR partition and at the sametime deletes the single volume partition table (for the partition starting at LBA 264192 which was earlier written by PW scan at LBA 2), this process will rewrite the partition table for that volume. In addition you have also assigned a drive letter to that drive)

This in all probability should bring your drive back alive.

Caution: In all these steps, make sure that you are performing all operations on your 3 TB external drive and not on your system drive or any other external drive. In fact plug out all other external drives.

If this experiment succeeds we will truly have a unique way of dealing with this problem.

Thank you for cooperating with this experiment.