Logical Disk Partitions Are Lost or Damaged After You Upgrade from Windows NT 4.0 to Windows 2000 (323231)

SYMPTOMS

When you use Windows 2000 Disk Management to try to create or delete a logical drive in an extended partition after you upgrade from Microsoft Windows NT 4.0 to Windows 2000, you may receive the following error message:

The Server Threw an Exception

After you receive this error message, logical disk partitions on the extended partition may be lost or damaged. This problem only occurs if one of the following conditions exists:

Drive translation is turned off in the controller BIOS.
The drive is moved to a position on the controller (typically upper SCSI IDs) where drive translation is not performed. Note that on some computers or controllers, drive translation options are not available.

CAUSE

This problem may occur because Windows 2000 does drive translation differently than Windows NT 4.0. Windows 2000 typically obtains disk geometry information for SCSI disks from the BIOS of the SCSI adapter for the disk. If the SCSI adapter BIOS is not turned on, Windows 2000 cannot obtain geometry information in this way and assumes that there are 255 heads and 63 sectors for each track.

Windows NT 4.0 performs the same kind of computation when geometry information is not available, but uses smaller default values for the number of heads (64) and sectors for each track (32).

The differences in disk geometry causes problems because Disk Management must modify several partition tables when it adds and removes logical drives.

RESOLUTION

Service Pack Information

To resolve this problem, obtain the latest service pack for Microsoft Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to Obtain the Latest Windows 2000 Service Pack

Hotfix Information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

   Date         Time   Version        Size      File name
   --------------------------------------------------------
   Jul-25-2002  13:33  5.0.2195.5912  34,384    Claspnp.sys
   Jul-30-2002  14:26  5.0.2195.5986  30,288    Disk.sys

Apply this hotfix before you add or delete logical drives on the Windows 2000-based computer.

NOTE: To help recover the missing or damaged partition tables, you must contact Microsoft Product Support Services (PSS). For information about how to contact PSS, visit the following Microsoft Web site:

http://support.microsoft.com/directory/question.asp