Internal HDD D: Drive Disappeared

Hi people. I am the administrator on my windows vista ultimate 64-bit computer, SP 1. The computer has 2 physical internal hard drives, in RAID 0. Each 500 GB so I had a total of 1TB. My documents were but onto my D Drive incase the C Drive failed.


There is alot to read below, please help me. If its too much, here is a quick summary. I played around with net user on cmd, my password changed. I used offline nt password and registry editor to reset it but now my D Drive has gone.


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DETAILS
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I had 1 standard user and 2 administrator accounts on the computer. although one of the admin accounts was for a quick test, and I wanted to make it a standard account. but I had a major problem that I couldnt fix, the standard accounts kept giving an error about connecting to Group Service Policy Client and it never logged on. So I used the admin account. The password to my normal, admin account was the number, 1. The second account had the password, pass. Finally the last account is the account I needed to access with an unknown password, only my friend knew it and he was away. I needed to find the password of this standard user, not change it but view it. I attempted the Net User command in cmd. It listed the users. I typed Net User followed by the user name, then x.

For example, net user john x

It said

"
The syntax of this command is:

NET USER
[username [password | *] [options]] /DOMAIN
username <password | *> /ABO [options] /DOMAIN
username /DELETE /DOMAIN
username | ALL>
"

After this point, I wasn't sure what to do because I had read that it will ask me input a new password. This wasn't what I was looking for but it would have been handy. so I exit, and I logged off my account, and went to the account with the password 'pass'. On this account, I made it a standard user, so I wouldnt be able to access it. then when I went back to my normal accound, the password 1 wasnt working. I tried 'x', 1, pass, net user, nothing worked. And I couldnt access the standard account because of the error. Eventually I booted the computer in safe mode, here I COULD access the standard accounts but I couldnt modify any account settings. I noticed that only my Local Disk (C:) was showing, and my CD Drive, but not my D Drive.

So I downloaded a bootable cd, Offline NT Password & Registry Editor. A friend who is a computer technician helped me through the process, and I managed to reset the password and gain access to the admin account. And now, I havent been able to find the D Drive. The paths are still in the history, I had a folder there called My Data, when I type D:\ it lists D:\My Data, D:\My Documents. All my documents and videos and pictures and music and work were on this drive. I went to computer management, and under "Disk Management", it shows this:


Disk 0 (shows a BLUE bar here)
Basic (C:)
465.76 GB 451.21 GB NTFS
Online Healthy (System, Boot, Page File, Active, Crash Dump, Primary Partition

Next to this, it shows the recovery drive, E:


Under this, is shows

Disk 1 (shows a BLACK bar here)
Basic
465.76 GB 451.21 GB
Online Unallocated

Next to this it shows another partition of this drive which is the same size as the recovery partition on the C drive. This says its healthy (EISA Configuration).




My D: is missing and I really need it, I dont know if it was encrypted or anything, I want to try using Get Data Back, the software. If it doesnt work, ill see if there is any way to decrypt it if it is encrypted. This is extremely urgent, and any help will be VERY MUCH appreciated.

Thank you.