Retrieving Data from Partitioned and Formatted Drives


Retrieving Data from Partitioned and Formatted Drives

When a hard disk, floppy disk, or removable-media drive has been formatted, its file allocation table, which is used by programs such as Norton UnErase or VCOM System Suite's FileUndeleter to determine the location of files, is lost. If a hard drive has been repartitioned with FDISK or another partitioning program (such as Windows 2000/XP's Disk Management), the original file system and partition information is lost (as is the FAT).

In such cases, more powerful data-recovery tools must be used to retrieve data. To retrieve data from an accidentally formatted drive, you have two options:

  • Use a program that can unformat the drive.

  • Use a program that can bypass the newly created FAT and read disk sectors directly to discover and retrieve data.

To retrieve data from a drive that has been partitioned, you must use a program that can read disk sectors directly.

Norton Unformat and Its Limitations

Norton Utilities and Norton SystemWorks offer Norton Unformat, which can be launched from the bootable CD to unformat an accidentally formatted FAT drive. However, Norton Unformat has significant limitations with today's file systems and drive types, including the following:

  • Norton Unformat doesn't support NTFS drives. This means many Windows 2000 and XP-based systems can't use it for data recovery.

  • Norton Unformat cannot be used with drives that require device drivers to function, such as removable-media drives.

  • Norton Unformat works best if the Norton Image program has been used to create a copy of the FATs and root directory. If the image file is out-of-date, Unformat might fail; if the image file is not present, Unformat cannot restore the root directory and the actual names of folders in the root directory will be replaced by sequentially numbered folder names .

  • Norton Unformat cannot copy restored files to another drive or folder. It restores data back to the same drive and partition. If Unformat uses an out-of-date file created by Norton Image to determine where data is located, it could overwrite valid data on the drive being unformatted.

For these reasons, Norton Unformat is not the most desirable method for unformatting a drive. You can use the powerful, but completely manual, Norton Disk Editor (DISKEDIT) to unformat a drive or retrieve data from a formatted drive, but other alternatives are simpler.

Retrieving Lost Data to Another Drive

Many products on the market can retrieve lost data to another drive, even if the data loss was due to accidental formatting or disk partitioning. One of the best and most comprehensive products is the EasyRecovery product line from Ontrack DataRecovery Services, a division of Kroll Ontrack, Inc. The EasyRecovery product line includes the following products:

  • EasyRecovery DataRecovery. Recovers data from accidentally formatted or deleted hard, floppy, and removable-media drives and repairs damaged or corrupted Zip and Microsoft Word files. Local and network folders can be used for recovered files.

  • EasyRecovery FileRepair. Repairs and recovers data from damaged or corrupted Zip and Microsoft Office (Word, Excel, Access, PowerPoint, and Outlook) files. Local and network folders can be used for recovered files.

  • EasyRecovery Professional. Combines the features of DataRecovery and FileRecovery and adds features such as file type search, RawRecovery, and user -defined partition parameters to help recover data from more severe forms of file system corruption and accidental partitioning. A free trial version displays files that can be recovered (and repairs and recovers Zip files at no charge); it can be downloaded from the Ontrack website (http://www.ontrack.com).

An earlier version of EasyRecovery Data Recovery Lite can recover up to 50 files and is included as part of VCOM's System Suite (previously sold by Ontrack).

When you start EasyRecovery Professional, you can choose from several recovery methods , including these:

  • DeletedRecovery. Recovers deleted files

  • FormatRecovery. Recovers files from accidentally formatted drives

  • RawRecovery. Recovers files with direct sector reads using file-signature matching technology

  • AdvancedRecovery. Recovers data from deleted or corrupted partitions

In each case, you need to specify another drive to receive the retrieved data. This read-only method preserves the contents of the original drive and enables you to use a different data-recovery method if the first method doesn't recover the desired files.

Which options are best for data recovery? Table 11.1 shows the results of various data-loss scenarios and recovery options when EasyRecovery Professional was used to recover data from a 19GB logical drive formatted with the NTFS file system under Windows XP.

Table 11.1. Data Recovery Options and Results with EasyRecovery Professional

Type of Data Loss

Data Recovery Method

Data Recoverable?

Details

Notes

Deleted folder

DeletedRecovery

Yes

All files recovered.

All long file and folder names preserved.

Formatted drive (full format)

FormatRecovery

Yes

All files recovered.

New folders created to store recovered files; long filenames preserved for files and folders beneath root folder level.

Logical drive deleted with Disk Management

AdvancedRecovery

Yes

All files and folders recovered.

All long file and folder names preserved.

Formatted drive with new data copied to it

FormatRecovery

Partial

Files and folders that were not overwritten were recovered.

Long filenames and folders preserved.

Formatted, repartitioned drive reformatted as FAT32 (117MB Disk 1)

AdvancedRecovery

No

Could not locate any files to recover.

 
 

RawRecovery

Partial

Nonfragmented files recovered.

Original directory structure and filenames lost; each file type stored in a separate folder and files numbered sequentially.

Formatted, repartitioned drive formatted as NTFS (18.8GB Disk 2)

AdvancedRecovery

No

Could not locate any files to recover.

 
 

RawRecovery

Partial

Nonfragmented files recovered.

Original directory structure and filenames lost; each file type stored in a separate folder and files numbered sequentially.


As Table 11.1 makes clear, as long as the data areas of a drive are not overwritten, complete data recovery is usually possibleeven if the drive has been formatted or repartitioned. Thus, it's critical that you react quickly if you suspect you have partitioned or formatted a drive containing valuable data. The longer you wait to recover data, the less data will be available for recovery. In addition, if you must use a sector-by-sector search for data (a process called RawRecovery by Ontrack), your original folder structure and long filenames will not be saved. You will therefore need to re-create the desired directory structure and rename files after you recover thema very tedious process.

Tip

If you use EasyRecovery Professional or EasyRecovery DataRecovery to repair damaged Zip or Microsoft Office files, use the Properties menu to select a location for repaired files (the original location or another drive or folder). By default, repaired Outlook files are copied to a different folder, whereas other file types are repaired in place unless you specify a different location.


As you can see from this example, dedicated data-recovery programs such as Ontrack EasyRecovery Professional are very powerful. However, they are also very expensive. If you have Norton Utilities or Norton SystemWorks and don't mind taking some time to learn about disk structures, you can perform data recovery with the Norton Disk Editor.




Upgrading and Repairing Microsoft Windows
Upgrading and Repairing Microsoft Windows (2nd Edition)
ISBN: 0789736950
EAN: 2147483647
Year: 2005
Pages: 128

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