How to Use Convert.exe to Convert a Partition to the NTFS File System

For a Microsoft Windows 2000 version of this article, see 214579 .


Windows XP supports two disk file systems: the file allocation table (FAT) file system and the NTFS file system. This article explains how to convert a FAT partition into an NTFS partition and discusses the considerations that you must take into account.

More Information

Windows XP includes the Convert.exe utility for converting a FAT partition to an NTFS partition. Convert.exe is simple to use, but there are some limitations that you should consider before using the utility.

You should consider the following limitations before you convert a FAT partition to NTFS:

  • The conversion is a one-way process. After you convert a partition to NTFS, you cannot convert the partition back to FAT. To restore the partition as a FAT partition, the partition would have to be reformatted as FAT, which erases all data from the partition. Data would then be restored from backup.
  • Removing Windows XP to revert to Windows 98 or to Windows Millennium Edition (Me) is not an option after you convert any drive on the computer to NTFS.
  • You cannot convert the system partition of a RISC-based computer to NTFS. The ARC specification requires that the system partition be FAT. It is possible to create a small (1-megabyte) FAT partition for the system partition and then install Windows on an NTFS partition (the boot partition).
  • Convert.exe requires that a certain amount of free space be present on the drive in order to convert the file system.For additional information about the amount of free space that is required for a conversion, click the article number below to view the article in the Microsoft Knowledge Base:

    156560 Free Space Required to Convert FAT to NTFS
NOTE: Although there is little chance for corruption or data loss during the conversion from FAT to NTFS, it is a good idea to perform a full backup of the data on the drive that it is to be converted before you run the convert command. Before you proceed, it is also a good idea to verify the integrity of the backup.

To convert a FAT partition to NTFS, follow these steps:

  1. Click Start, click Run, type cmd, and then click OK.
  2. At the command prompt, type CONVERT driveletter: /FS:NTFS.
  3. Convert.exe attempts to convert the partition to NTFS.
While Convert is running, you may receive the following error message:

Convert cannot gain exclusive access to the driveletter:, so it cannot convert it now. Would you like to schedule it to be converted the next time the system restarts (Y/N)?
You receive this error message under any of the following three conditions:

  • If you run the CONVERT command while the current directory is on the drive that is to be converted (for example, if you type CONVERT F: /FS:NTFS at the F:\> prompt).

    To resolve this, either click Yes in the error message and then restart the computer, or change to a directory on another drive and retype the command.
  • If a program has a file open on the drive that is to be converted.

    To resolve this, either click Yes in the error message and let the drive be converted next time the computer is restarted, or close any programs that may be using files on the drive. Remember that this also applies to users who connect to files over the network and to a paging file that resides on the drive.
  • If you attempt to convert the partition from which the operating system is running.

    It is not possible to convert the boot partition while the operating system is running. To convert the boot partition, it is always necessary to run the CONVERT command, click Yes in the error message, and then restart the computer. The partition is converted the next time the computer is restarted. As an alternative, you can start the computer in an installation of Windows XP that is on a different partition, and convert the boot partition from that installation of Windows XP.
For additional information about the differences between the FAT and NTFS file systems, along with the advantages and disadvantages of each, click the article number below to view the article in the Microsoft Knowledge Base:

100108 Overview of FAT, HPFS, and NTFS File Systems

Article ID: 314097 - Last Review: Oct 23, 2008 - Revision: 1