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converted ntfs to fat32 can i revert

By krisreply ·
hi
I could really appreciate some tech advice as I have a big problem i ruined my entire media collection, i have a usb maxtor 350gb external hd which i had created 2 partitions both NTFS with partition magic 8 as it supports creation of large partitions. 1 partition i have put my audio on the other my video. i then converted both partitions to FAT32 with partition magic as it allows u to do this windows xp pro doesnt.
Now even though i see directory's and files, files are inaccessible and error say files and directory's are corrupted.

ok so i have now 2 Fat32 partitions, was 2 NTFS but converted them 1 by 1 using PM 8.0.(note conversion from NTFS to FAT32 is not possible in windows xp pro but is vise-versa).

Situation now is both drives appear to the eye to be ok, directory structures are readable and files are visible. Despite this the files cannot be read or moved neither can directory be moved, in attempt i receive corrupt file and directory error.

what i would like to know in order to recover my data as efficiently as possible should i:

a) Convert back to NTFS and attempt recovery of files, instead of using methed (b) because different partition types (FAT32) have different 'file allocation unit size' and think this may affect retrieval success rate.

b) Leave converted partition in current state (FAT32) and attempt recovery methods like RAW data recovery as data is recovered without assistance from Partition tables.

c) Use Windows System Restore, as the drive is being monitored by windows, to revert partition conversion. (i also wish to say the drive in question is not bootable just an externel USB MAXTOR HD 350GB split to into 2 partition via pmagic which supports large partition creation.)

Which method would be considered the better without compromising any more dataloss/curruption as the drive stands, method A, B or C.

I would prefer method 'C' but am not sure if System Restore can restore for this kind of scenario involving a partition conversion, on restore to be reverted to previous partition state as NTFS.

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Re: Converted NTFS to FAT32 can i revert?

Why you want to balls up your system is any body's guess.
When you get it all working BACK IT UP. That way you have something to fall back on. :)

Read below and digest the info. It will help with your issue.

How to convert a FAT16 volume or a FAT32 volume to an NTFS file system in Windows XP

INTRODUCTION
Microsoft Windows XP supports the following three file systems for fixed disks:
? FAT16
? FAT32
? NTFS
We recommend that you use NTFS with Windows XP because of its advanced performance, security, and reliability features. This article describes how to convert a FAT16 volume or a FAT32 volume to NTFS.

Requirements
Before you start to convert a FAT volume or a FAT32 volume to NTFS, consider the following limitations and requirements:
? UDF and CDFS are only used with optical media and cannot be converted to NTFS.
? FAT12 is the only format used on floppy diskettes.
? Some earlier programs that were not written for Microsoft Windows NT 4.0 or for Microsoft Windows 2000 may exhibit slow performance after you convert the FAT32 file system to NTFS. This issue does not occur on a clean partition of NTFS.
? You can use the convert command (Convert.exe) to convert an existing FAT volume or FAT32 volume to NTFS. Because this conversion retains all your files (unlike a format operation), use Convert.exe when you want to keep existing files on your volumes intact.
? The conversion to NTFS is a one-way process. After you convert a drive or a partition to NTFS, you cannot convert it back to FAT or to FAT32. To restore the volume to the previous file system, you must reformat it as FAT or as FAT32. This action erases all existing data including your programs and personal files. In this case, you must either restore your data from a backup, or reinstall your operating system and programs.
? Convert.exe requires that you have some free space on the drive or on the partition to convert it. If Convert.exe determines that there is not sufficient free space on the volume, it does not convert the volume.
? If you run other Microsoft Windows operating systems on your computer in addition to Windows XP, note the following issues:
? Only Windows 2000 and Windows XP have full access to files on an NTFS volume.
? Windows NT 4.0 Service Pack 4 (SP4) or later can access files on an NTFS volume. However, there are some limitations with files that are stored by using features from the latest version of NTFS.
? Microsoft Windows Millennium Edition (Me), Microsoft Windows 98 Second Edition and earlier, and MS-DOS cannot access files on an NTFS volume.

How to convert a FAT volume or a FAT32 volume to NTFS
Note Although the chance of corruption or data loss during the conversion is minimal, we recommend that you perform a backup of the data on the volume that you want to convert before you start the conversion.

To convert an existing FAT or FAT32 volume to NTFS, follow these steps:
1. Click Start, point to All Programs, point to Accessories, and then click Command Prompt.
2. At the command prompt, type the following, where drive letter is the drive that you want to convert:
convert drive letter: /fs:ntfs
For example, type the following command to convert drive E to NTFS:
convert e: /fs:ntfs
Note If the operating system is on the drive that you are converting, you will be prompted to schedule the task when you restart the computer because the conversion cannot be completed while the operating system is running. When you are prompted, click YES.
3. When you receive the following message at the command prompt, type the volume label of the drive that you are converting, and then press ENTER:
The type of the file system is FAT.
Enter the current volume label for drive drive letter
4. When the conversion to NTFS is complete, you receive the following message at the command prompt:
Conversion complete
5. Quit the command prompt.

Troubleshooting
? When you try to convert a volume to NTFS, you receive the following error message at the command prompt:
Convert cannot gain exclusive access to the drive letter drive, so it cannot convert it now. Would you like to schedule it to be converted the next time the system restarts? <Y/N>
This issue occurs when the volume that you are trying to convert is in use, for example, if the drive that you want to convert is the same drive where Windows XP is running.

To resolve this issue, type Y at the command prompt. The volume or drive is converted to NTFS the next time that you start your computer.
? When you try to convert a volume to NTFS, you receive the following error message at the command prompt:
Convert cannot run because the volume is in use by another process. Convert may run if this volume is dismounted first. ALL OPENED HANDLES TO THIS VOLUME WOULD THEN BE INVALID. Would you like to force a dismount on this volume? <Y/N>
This issue occurs when there are files that are being used on the volume that you are trying to convert. This includes files that are accessed by users over the network.

To resolve this issue, use one of the following methods:
? Quit all the programs that are using the files on the drive, and then type y at the command prompt to convert the drive to NTFS.
? At the command prompt, type Y.
You receive the following error message:
Convert cannot gain exclusive access to the drive letter drive, so it cannot convert it now. Would you like to schedule it to be converted the next time the system restarts? <Y/N>
Type Y at the command prompt. The volume or drive is converted to NTFS the next time that you start your computer.

REFERENCES
For more information about Convert.exe, follow these steps to view a list of command line parameters:
1. Click Start, point to All Programs, point to Accessories, and then click Command Prompt.
2. At the command prompt, type help convert, and then press ENTER.
A list of command line parameters for Convert.exe appears. For more information about how much free space is required to convert FAT to NTFS, click the following article number to view the article in the Microsoft Knowledge Base:

Free Space Required to Convert FAT to NTFS

SUMMARY
The conversion of a disk partition from the FAT file system to NTFS requires a certain amount of free disk space be available in order to build the NTFS disk structures. This article provides a description of the process Convert.exe uses to convert FAT to NTFS and discusses the space required for conversion.
MORE INFORMATION
FAT and NTFS use very different on-disk structures to represent the allocation of space for files. These structures are often referred to as meta-data or file system overhead.

The FAT file system's meta-data consists of a boot sector, one or more File Allocation Tables, a fixed-size root directory structure, and a variable amount of space for each sub-directory related to the number of files in the sub-directory.

Another kind of overhead associated with both FAT and NTFS is related to the fact that both file systems allocate disk space in clusters of a fixed size. The exact size of these allocation units or clusters is determined at format time, and the defaults are dependent on the size of the volume. The default cluster size for NTFS is smaller than the default for FAT on similarly sized volumes.

Because space for file data can only be allocated in whole cluster amounts, even a one byte file will end up using a cluster's worth of disk space on a FAT volume. The NTFS case is similar, but slightly more complicated and will not be covered in detail in this article.

Like FAT, NTFS has a certain amount of fixed size overhead and a certain amount of per-file overhead. In order to support the advanced features of NTFS, such as recoverability, security, support for very large volumes, and so forth, the NTFS meta-data overhead is somewhat larger than the FAT meta- data overhead. On the other hand, because NTFS cluster overhead is smaller than FAT cluster overhead, it is often possible to store as much, if not more data on an NTFS volume as on a FAT volume, even without using NTFS file compression.

In order to guard against the possibility of corruption caused by failure during conversion, Convert.exe must build the NTFS meta-data using only that space which is considered free space by the FAT file system. In this way, if the conversion fails to complete, the FAT representation of the user files is still valid. Complicating this strategy is that one sector of NTFS data must occupy a specific location on the disk, and a very limited number of other structures must occupy contiguous sectors.

The general outline of the conversion process is as follows:

1. Create holes (that is, relocate FAT clusters) for the fixed-location NTFS structure and other contiguous data (if necessary) and save the new FAT. If the necessary sectors cannot be made available due to being unreadable, for example, the conversion process will fail and the FAT volume will remain in the same state it was in before the attempted conversion.

2. Create NTFS elementary data structures in FAT free space. These are the fixed-size tables and structures common to any NTFS volume. The size of these tables may vary depending on the size of the volume, but do not depend on the number of files on the volume.

3. Create the NTFS master file table and directory listings in the FAT free space. The space required for this step is variable and depends on the total number of files on the FAT volume.

4. Mark as free in the NTFS bitmap those NTFS clusters being used by FAT- specific structures. After the conversion is complete, the FAT meta-data overhead can be reclaimed as free space to NTFS.

5. Write NTFS boot sector. This is the final action that causes the volume to be recognized as NTFS rather than FAT. If the conversion fails at any step prior to this, the volume will still be a valid FAT volume and will be recognized as such.
Because a crash can occur at any time, the process described above minimizes the chance of disk corruption.

NOTE: Almost all writes are to FAT free space, so a failure will preserve the FAT intact.

The only times at which we write to non-free space, for example, the times at which a failure might cause problems are:
? At the end of step 1, when CONVERT overwrites the FAT. The algorithm for relocating clusters guarantees that if a failure does take place during this stage, CHKDSK will be able to fix the disk without any loss of data.
? In step 5, while writing the boot sector. If a failure occurs during this step, and the volume being converted is the system partition (the active, primary partition used to boot the system) there is a chance that the system could be left in a state where it would not start. In the unlikely event that this takes place, it should still be possible to start the system using a boot floppy disk.
Convert.exe performs a computation based on the number of preexisting files on the FAT volume and size of the volume to figure out how much free space is required before starting the conversion process. For standard hardware (hard drives with 512 bytes per sector) the equation boils down to the following:

1. Start by taking the size of the volume, in bytes, and dividing by 100. If this value is less than 1,048,576, use 1,048,576. If it is larger than 4,194,304, use 4,194,304.

2. Add to the above the size of the volume in bytes divided by 803.

3. Add to the above the number of files and directories on the volume multiplied by 1280.

4. Add to the above 196,096.
In addition to the above, if there is extended attribute information on the FAT volume, Convert.exe will take into account the additional space that will be required. Extended attribute information is normally not present and would only be a consideration if the system had been running OS/2 and extended attributes were in use.

The above computation closely mirrors the computation performed by Convert.exe. The exact result obtained on a given system may differ slightly.

NOTE: This is the free space required by Convert.exe before it will attempt a conversion. The computation includes an allowance for the possibility that bad sectors may be encountered in the FAT free space. However, in cases where a volume has just enough free space to begin the conversion, and a significant fraction of drive space is discovered to be unusable, the conversion process may fail. As discussed above, this should not result in any disk corruption. The volume should automatically fall back to being recognized as FAT.

Please post back if you have any more problems or questions.
If this information is useful, please mark as helpful. Thanks.

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System Restore will not do it for you....

by ThumbsUp2 In reply to converted ntfs to fat32 c ...

That will only reverse changes to the registry. It does nothing to files, folders or structure of HDD's.

I don't know what ever possessed you to convert from NTFS back to FAT32 in the first place, but you're stuck now. Your best bet is to attempt to copy the files to another type of storage, such as DVD/CD, make sure they're accessible that way, then format the external drives through Windows. Since you have two partitions, you'll need to format each.

If you're unable to reliably burn/copy the files to another type of storage media while in WinXP, you might try using a Linux Live CD, such as UBUNTU, to boot the computer with and THEN try to burn (copy) them to DVD/CD. Often booting to some form of Linux Live will allow you to access files that WinXP says are not accessible.

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