Support for Windows XP has ended
Microsoft ended support for Windows XP on April 8, 2014. This change has affected your software updates and security options. Article ID: 140060 - View products that this article applies to. System TipThis article applies to a different version of Windows than the one you are using. Content in this article may not be relevant to you.Visit the Windows 7 Solution Center This article was previously published under Q140060 SYMPTOMS When you access a floppy disk, you may receive one of the
following error messages: A:\ is not accessible. The device is not ready. -or- Disk is not formatted The disk in drive A is not formatted. Do you want to format it now? -or- STOP: The disk media is not recognized, it
may not be formatted. CAUSE This problem occurs on disks that do not contain a media
descriptor byte in the BIOS parameter block (BPB) of the boot sector. Some
older preformatted floppy disks do not contain a media descriptor byte. Older
product disks may also not have the media descriptor byte. The media descriptor indicates the type of medium currently in a drive. With MS-DOS and Windows 95, you do not have to set the media descriptor byte. Therefore this problem does not occur with these older operating systems. The media descriptor byte is located in the BPB of the boot sector at offset 21 (15h) and in the first byte of each FAT on the disk. RESOLUTIONTo resolve this problem, re-format the floppy disk with
Windows 98, Windows Millennium Edition, Windows NT, Windows 2000, Windows XP,
or Windows Server 2003. WORKAROUNDWarning: This workaround is for advanced users only. This workaround
involves using a disk sector editor to modify the media descriptor byte on the
floppy disk. Misuse of a disk sector editor may make all the data on the drive
or volume permanently inaccessible. Disk sector editors function at a level
"below" the file system, so the typical checks for maintaining disk consistency
do not apply. This provides you direct access to every byte on the physical
disk regardless of access credentials. Therefore, you can damage or permanently
overwrite critical on-disk data structures. Use this workaround at your own
risk. To work around this problem, use a disk sector editor to change the BPB media descriptor byte to the appropriate value. For example, you can use the DiskProbe tool to do this on a Windows NT 4.0-based, Windows 2000-based, Windows XP-based, or Windows Server 2003-based computer. DiskProbe (Dskprobe.exe) is included with the Windows Support Tools for Windows XP Professional and Windows XP 64-Bit Edition, the Windows 2000 Support Tools, and Windows NT 4.0 Resource Kit Support Tools. The following table lists the most common media descriptor bytes: Byte Capacity Media Size and Type ------------------------------------------------- F0 2.88 MB 3.5-inch, 2-sided, 36-sector F0 1.44 MB 3.5-inch, 2-sided, 18-sector F9 720K 3.5-inch, 2-sided, 9-sector F9 1.2 MB 5.25-inch, 2-sided, 15-sector FD 360K 5.25-inch, 2-sided, 9-sector FF 320K 5.25-inch, 2-sided, 8-sector FC 180K 5.25-inch, 1-sided, 9-sector FE 160K 5.25-inch, 1-sided, 8-sector FE 250K 8-inch, 1-sided, single-density FD 500K 8-inch, 2-sided, single-density FE 1.2 MB 8-inch, 2-sided, double-density F8 ----- Hard disk
addr data:
0000 EB 3C 90 4D 53 44 4F 53 35 2E 30 00 02 01 01 00
0010 02 E0 00 40 0B F0 09 00 12 00 02 00 00 00 00 00
xx <---- This byte above XX is the media descriptor
byte and is at offset hexadecimal 21 (15h).
MORE INFORMATION For additional information, click the following article
number to view the article in the Microsoft Knowledge Base: 301423
(http://support.microsoft.com/kb/301423/EN-US/
)
HOW TO: Install the Windows 2000 Support Tools to a Windows 2000 Server-Based Computer
306794
(http://support.microsoft.com/kb/306794/EN-US/
)
How to Install the Support Tools from the Windows XP CD-ROM
206848
(http://support.microsoft.com/kb/206848/EN-US/
)
Windows NT Service Pack 4.0 Tools Not Included on CD-ROM
PropertiesArticle ID: 140060 - Last Review: December 3, 2007 - Revision: 4.7 APPLIES TO
|
|
