FREE NTFS Partition Repair Data Recovery Software
January 25, 2008
Hey Everyone! Thanks for all the positive emails and phone calls. One email from Jim L in Dallas Texas asks: “you talk about partition repair, but the software doesn’t actually repair the partition, it recovers files from it. Is there anything out there that does repair partitions?” Well Jim while most people are happy to just get their data back from a damaged partition, we do have a tool for those brave souls that want to actually REPAIR a partition.
Dick Correa our chief programmer was kind enough to release a tool he created that does in fact REPAIR NTFS partitions. This software is free to our readers and can be gotten off of our website. The link is at the bottom of this post. Keep in mind that DTI is not responsible for any data lost from misuse of this tool. It is extremely powerful. Now that the lawers are happy, here is Dick’s post:
NTFS Partition Recovery with Free Partition RecoveryAll things must start somewhere, when it comes to operating systems’; the partition sector is the single most important component in the boot sequence. When the partition sector is missing, corrupt, or set up improperly it can wreak havoc with the booting of your operating system. The partition sector is vulnerable to virus attacks, operating system anomalies, bad sector reads, and an ever increasing set of tools, fdisk included, that when used incorrectly can and will totally destroy an operating systems boot sequence.
In order to more clearly understand how the partition sector fits into the boot sequence, the following is a standard garden variety boot up.
When you turn on your computer several things happen. The first of which is the BIOS (Basic Input Output System) is executed by the CPU (Central Processing Unit). The CPU knows to load the BIOS on power up as there is a flag set at power on. The BIOS then jumps to a set of routines that will execute the POST (Power On Self Test). The POST will look at memory, some peripheral devices, and do some other house keeping procedures. The most important of these is determining the boot device. The boot device is stored in non-volatile read/write memory. If the boot device is set to a hard drive, then an industry standard interrupt 0×19 is called. This routine loads the first 512 bytes of the boot device, which in this case the hard drive, into memory location 0×7C00. The 512 bytes is a standard sector size. It then jumps to that address (0×7C00) and executes whatever it finds there.
If all goes well, the set of instructions executed will look at the partition entry data. The partition entry data is used to determine which partition is the boot partition. If it finds a boot partition in the partition entry list the instructions will then load a secondary set of instructions which the partition entry has pointed to. In the case of Windows the OS (Operating System) pre loader is now loading itself into memory. This type of OS loader is called a two phase loader and is very common. Take a look at the table below to help better understand the role of the partition sector entry data.
The format of a partition sector entry is as follows:
1.) Byte 1 Boot Partition Indicator (0×80 is bootable, 0×00 is not)
2.) Byte 2 Starting Head of the partition (255 or less)
3.) Byte 3-4 Starting Sector and Cylinder of the partition
This is set up as 10 bits for the Cylinder and
6 bits for the Sector (Sector Max 63, Cylinders Max 1024)
4.) Byte 5 File System Type (NTFS, FAT32 etc)
5.) Byte 6 Ending Head of the partition (255 or less)
6.) Byte 7-8 Ending Sector and Cylinder of the partition
This is set up as 10 bits for the Cylinder and
6 bits for the Sector (Sector Max 63, Cylinders Max 1024)
7.) Bytes 9 -12 Relative Sector to the partition sector. In other
words, where the actual partition starts.
8.) Bytes 13-16 Total sectors for this partition.
If any of this data is outside the stated parameters the partition will fail and consequently the boot sequence will stop. In order to clearly understand what happens when the partition sector is corrupt or damaged, the following is a list of scenarios.1. Boot Failure: System Halted
An error message that comes from the BIOS. Certain BIOS versions, especially the most recent revisions, take a look at the partition sector. The BIOS will perform some preliminary tests and one of the tests is the Partition Identifier. At the end of every partition sector is the value 0xAA55. If this indicator is missing then the BIOS assumes that this is not a partition sector and the aforementioned error message will be issued.
2. System reboots over and over
Although this is not an error message, it can happen if the relative sectors point to an invalid OS pre loader. A trap is set and if the data that is loaded is not executable machine most BIOS’s will reboot.
3. Invalid Partition Table
This error message comes from the partition boot code. If there are no boot devices then the boot code will enter an infinite loop after this message is displayed.
4. Error Loading Operating System
After a valid partition is found the LBA sector pointed to by the partition entry table will be loaded using INT 13. This is the operating system loader. If the code cannot be loaded into memory then the above message is normally displayed.
5. Missing Operating System
Once the operating system boot code is loaded it is checked for the 0xAA55 identifier in the same manner that the partition sector is tested. If this test fails, then the above message will be displayed.
Over the years the BIOS writers have gotten smarter, personal computer as well as operating system standards have been set and are normally followed. So many of the messages, as well as error checking is now handled by the BIOS. The messages I have mentioned are just a few, but, are very common; however, from BIOS to BIOS the messages as well as the error handling can differ greatly.
As you can clearly see the partition sector is of primary importance in the boot sequence. Without it nothing happens. In the future there may be ways to overcome the use of a partition sector, one would be to store the partition entry data in the BIOS, this would eliminate boot sector viruses as well as the possibility that the boot sector goes bad and becomes unreadable. However for now, we will work with what we have. The next segment will discuss how to do partition recovery using a simple piece of software.
How To Use The Software
Free Partition Recovery is an extremely powerful tool for anyone to use but this statement must be caveated with the fact that with power comes a degree of responsibility. In other words, use this tool with extreme caution as it can destroy your file system to the point of massive and possibly permanent data loss. That being said lets take a look at how we can put this tool to good use.
First, the software should be run from a master drive. There should be two drives in the system, your boot drive from where the software is executed, and the damaged drive. The damaged drive being the one with the corrupt or missing partition. Free Partition Recovery is designed to work on Windows XP type operating systems, so make sure that you have unzipped the file onto that type of operating system.
Once the Free Partition Recovery has been executed you will see in Figure 1.
Figure 1
The top row displays all the physical drives currently active in your system. This will also include any external devices that can be mounted as a physical block device. An example of this would be the 80 GB Maxtor USB device. Once you choose a physical drive all partition entry data will be displayed as in Figure 2.
Figure 2
The partition entry data for this particular drive gives us a clear example of a drive that has been configured with one NTFS logical drive with the standard offset of 63 sectors, start head and sector of 1 and ending cylinder of 1023. These are classic values for a normal single logical drive setup.
The other three entries are clear and not in use. These entries will be ignored by the OS loader. There is one other important item in this configuration. On the far left of Figure 2 of the first partition entry is the boot flag “No”. This indicates that this partition is ‘Not Bootable’. You can change that value buy using the drop down list (Figure 3)
Figure 3
Once you have configured all of the partition entries to reflect the correct values all you need do is press the “Write” button. You will be presented with the following message box in Figure 4. A word of caution, once you write the data down to the partition sector, you must live with it. Please exhibit extreme caution.
Figure 4
Hopefully this information as well as the software will help you recover your data. If you have any questions email support@dtidata.com or call 727-345-9665 Ext 236.
You can download the free NTFS partition repair software here. For more info about data recovery visit our home page.
[...] This software is free to our readers and can be gotten off of our website. The link is at the bottom of this post. Keep in mind that DTI is not responsible for any data lost from misuse of this tool. It is extremely powerful. … read more [...]
Have a 400 GB External harddrive stopped working suddenly , and display unformatted harddrivewhile connecting. So try to recover data using this tool
let’s try it out
good software in use all problem
good soft ware in usre some tine and test it
pls i need a data recovery software downlodable for toshiba pc A20 series.. i’ll gladly appreciate it if my request can be granted
dear author,
HI, i quite fresh for those recovery things. But i like to ask a question with my full hope, hope authors can answer my question.
Few week ago when i want to format my disk, because of crash of software and i ensure and purposely only format the C drive which is the window file system. What i did is, i configure the HDD in BIOS and i set the sequence of booting. But when i run the window xp booting the window shown my HDD only content no partition. In addition, it cannot boot up the window whatever i had never format the HDD before.
So can i know that your product can help me recover my lost partition and can show me how-to use this genius product?
Finally I hope my question can be answered by the authors soon. Thank you.
SAM
I read your direction on using your software, am I correct in saying
that I need to have another hard drive with a bootable OS to boot up the PC and use your software on the dead or almost dead hard drive? If thats so can I make abootable usb hard drive?
I read your direction on using your software, am I correct in saying
that I need to have another hard drive with a bootable OS to boot up the PC and use your software on the dead or almost dead hard drive? If thats so can I use it with a Live cd win xp or Bart pe disc?
In answer to your question Jeff, you are absolutely correct in your assumption that you may format and install an NT type OS onto a USB device. That device in turn may be used to boot from if the BIOS of the particular motherboard supports that type of functionality.
A word of caution however when installing. In order to avoid device confusion during the install it is prudent to only have the USB device plugged in. That way the data on any other hard drives cannot be “accidentally” compromised. I myself have sometimes mistaken one device for another and fdisked, formatted, and installed the OS on the wrong drive.
Hopefully, your solution will be able to bring your compromised file system back to life. If you have any more questions, please feel free to contact me.
One last note, I am finding that your situation is not unique. There are many technicians such as yourself who are in need of a software solution that can be used on any 80×86 based machine that may not be bootable. In addition the damaged machine may not have an operating system readily available that will support a particular data recovery tool. Mores the pity.
In answer to that, I have always been an enthusiastic advocate of stand alone DOS tools. I cut my PC programming teeth on DOS 3.3 and have loved it ever since. At this point in time I am in the design phase of some tools that will be standalone, bootable from a CD, or floppy, and have comparable functionality as many popular windows tools. Using FreeDOS, DJGPP, GRX and 25 years or programming experience I believe such a wonderful suite of tools can be developed that will run on any 80×86 machine. What a wonderful legacy for such a fine operating system. Hopefully I can find the time to develop these tools.
Prior to that however, I will try and write something similar the the free partition recovery tool using the above mentioned format. I do not have a time frame for release of such a tool, however, it is in my personal schedule.
Regards,
Dick Correa
Derek,
In answer to your question, you may most certainly use the Free Partition Recovery software on a Bart PE disk.. Jacqui Best has written a wonderful article on how to do this very thing. The link is below.
http://www.dtidata.com/resourcecenter/index.php?s=bart
This article refers to our Recover It All Pro software but the Free Partition Recovery will work just as well as the software is based on the same design and implementation standards.
I hope this helps you. If you have any questions please feel free to contact me.
Dick Correa
Hi, I just got a 2.5″ sata WD 120 GB 5400rpm hdd that I plan to use as an internal in my notebook. The drive makes a click x4 after powering up as external, but it’s not listed in “my computer”.
When I’m trying it as internal, I’m getting this message: “hard drive not recognized”.
I tried WD Data Lifeguard tools and the drive appears as “Generic External” when plugged in on usb post; also, Everest recognizes it.
What can I do to initialize the hard drive? Any tool to make it visible& format it?
Thanks,
Simona
How refreshing to have someone so knowledgable speak in plain english for all us ‘others’. Please, don’t ever stop.
Hello outthere!
I want to recover some datas in a non destructive way from a physical crashed drive, I just want to find these datas and transfer them to another drive. The crashed drive doesnt boot and I cant see anything on it except if I use some demo recovery tools. The drive contains bad sectors in some places and it seems to be physical damaged. Now here is why Im confused: Should I use the “Free NTFS Partition Repair Data Recovery Sofware” of yours on it or should I look somewhere else?
Im a bit confused..
Thanks for your help!
The instructions under Fig 3 say “Once you have configured all of the partition entries to reflect the correct values all you need do is press the “Write” button”. How do I know what are the correct values to enter?
did a windows update. when the computer rebooted, i got an error mesage to hit the ctl-alt-del keys. did this over and over, same result. the drive seems to be fine, all files are able to be read. can your utility help me fix this so i can boot from this drive into windows again??
Will the NTFS Repair feature handle this error ‘Inserting an indeix entry into index $o of file 25.’? I believe my C: drive NTFS suffered partial NTFS corruption following NDIS.SYS blue screen of death.
Symptom: Every time I cold boot the notebook, chkdsk will commence repair process. The screen displays ‘Inserting an indeix entry into index $o of file 25′ line after line until it said ‘Insufficient disk space to correct error in the index $o of file 25′. The Windows XP then allow me to logon but popup error message saying such and such folders is corrupted and unreadable. Some applications work fine but I noticed that while you can create/save file on C: drive, you can no longer delete nor change it. C: drive file system seems like being completely locked.
Any help is appreciated.
Well repairing the partition is not going to help because the partition is intact. If the partition was not the drive would not boot. It sounds as if you may have some bad sectors on the drive. It was also interesting when chkdsk indicated that there was not enough disk space on the drive to reallocate index allocations. Sometimes it is best to get your data off of the drive to another media before it goes bad. So, that said, I would back up whatever important data you have to another drive ( external usb, DVD, CD etc ) Then I would check the amount of space used on the drive. If you disk is totally full I would delete whatever you can live without and uninstall any programs you don’t use. The run chkdsk again. If chkdsk can not resolve you problem then I would suggest starting from scratch. Get all your data off of the drive, format the drive or even get a new one. Reinstall Windows and all of your programs, I do this once a year.
King,
After reading your message your problem exists with the file system itself and not the Master Boot record, or OS boot record. The Master File Table is corrupt and chkdsk is trying to repair. The situation with chkdsk is that it will destroy inodes and file pointers to the point where data cannot be recovered.
You sound like you may have one of two general problems. First, you may have bad sectors on the drive, and because they cannot be read it will show as a corrupt file system and chkdsk will try to run. Second, data was written to the MFT area of the file system and has corrupted the table. This can happen for so many reasons that it would not be prudent to list them here.
In order to solve this problem, I would pull the drive from the machine, place it in a USB sleeve and try to recover the data using DART for XP http://www.dtidata.com/free_data_recovery_software/DART.zip . If DART hangs then that usually means there are bad sectors on the drive, then you may want to use Speed Clone http://www.dtidata.com/free_data_recovery_software/Speed_clone_Demo.zip. To image the drive to another drive and then recover the data.
Hopefully these suggestions will help you. Good luck with your recovery, and as we always say “Don’t get eliminated!”
Dick
Thanks Dave and Dick Correa for your advice.
I am currently backing up all the data from the corrupted drive C: whilst I still have access to the system.
I did noticed disk space on C: slowly decreases from 600Mb to 300Mb as a result of inability to delete/create any file/folder nor flush the IE or Firefox cache. Evidence of disk lock being in play.
Strange is that chkdsk did not reported any bad sector nor hard error, so the disk seems to be still in good shape. But I will take your advice to offload all my data and rebuild the hard disk anew.
Before I rebuild the disk I shall give DART and Speed Clone a go and report back the finding.
Stay tune.
I have just had an unusual problem when inserting memory - and yes, i grounded myself the whole time - where the HDD boots then, it displays the WindowsXP start page - the one with the progress bar - and then reboots.
I can even call up the start menu, using F8 but it won’y any further
When i try run a repair using the XP Cd it says the HDD is unformatted, the partition is corrupted etc.,
Will this software help fix the HDD partition and boot XP correctly ?
I understand you can’t make any promises - a generalisation would be appreciative, and stop me going hysterical and insane.
Stephen,
I understand what you are going through. We will help in every way that we can! What type of computer is it? Is it a laptop or desktop? What type of hard drive is it - SATA, IDE, etc?
Do you have another computer available for recovery?
Please answer these questions and I can help you come up with a recovery game plan. The fact that your drive is recognized is a real good sign. Do not run any type of re-install or chkdisk or that could erase your existing data.
The Pc is a desktop and the HDD is an 80Gb IDE drive.
I have a couple of spare HDDs that I can install XP on
Unfortunately I’ve only got the one PC.
Re the chkdsk - don’t worry I haven’t done a thing as far as that’s concerned - my first concern is to see if there is a solution out there before i totally screw things up (laughing).