The Windows NT 4.0 Domain Controllers That Are Upgraded to Windows 2000 May Hang During the Final Phase of Setup

When you upgrade your computer from Windows NT 4.0 to Windows 2000 and the Winnt32.exe program is being run, the Windows NT 4.0 domain controllers that have large-sized Security Accounts Manager (SAM) account databases may seem to hang for excessive periods of time during the "Performing final tasks" phase of the upgrade. Under extreme circumstances, the computer may hang for up to 2.5 hours.

This behavior can occur during the "Performing final tasks" phase of Setup after approximately 90 percent of the "Saving settings" phase has completed. The "Performing final tasks" phase is one of the last phases of Setup before the Active Directory Installation Wizard starts and the Windows NT 4.0 registry-based SAM is converted to Active Directory.

To work around this behavior, complete the upgrade process without any administrator intervention. Eventually, the upgrade process completes and your computer returns to its normal state.

The domain controllers with SAM account databases that are 50 - 70 MB in size are the most susceptible to excessive upgrade times. The factors that can affect upgrade performance include the SAM size, the processor or disk subsystem performance, and the Registry Size Limit (RSL) settings.

To improve the upgrade performance on computers that have large SAM databases, you can make the following configuration changes:

1. Set the RSL in Windows 2000 to its maximum permitted value. One method is to set the RSL to 200 MB so that it is adjusted to 80 percent of PagedPoolSize when the computer restarts. The RSL must have a sufficiently high setting to enable the large-sized SAM upgrades to succeed. This setting is a key setting to improve upgrade performance.
   
   For additional information about increasing the RSL, click the article number below to view the article in the Microsoft Knowledge Base:
   124594  (http://support.microsoft.com/kb/124594/EN-US/ ) Understanding and Configuring Registry Size Limit (RSL)
2. Set the Pagefile size to the number that equals the amount of physical random access memory (RAM) multiplied by 120 percent.
3. Add any additional RAM to the server that is being upgraded to Windows 2000. For a Windows NT 4.0 primary domain controller (PDC) with a 30 MB SAM, 128 MB is the minimum amount of memory.
4. Shrink the SAM on the PDC by using method #3 in the following article:
   140380  (http://support.microsoft.com/kb/140380/EN-US/ ) User Account Database Fails to Shrink After Deleting Accounts
5. Add a new Windows NT 4.0 backup domain controller (BDC) to the domain, promote the BDC to a PDC, and then upgrade your computer to Windows 2000. The newly replicated SAM file should be less fragmented than the copy on the original PDC. Any reduction in SAM size can mean less memory use and faster upgrade performance. This method is particularly suitable when new hardware is being deployed concurrently with Windows 2000 domain controllers.

The following examples are taken from Windows NT 4.0 PDCs that have been upgraded to Windows 2000:

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

For additional information, click the article number below to view the article in the Microsoft Knowledge Base: To troubleshoot:

1. Examine the Windir\Debug\Dcpromos.log folder by using one of the following two methods:
   • Press Shift+F10 during the graphical user interface (GUI) mode setup to use a command prompt.
   • If you are unable to use the previous method and your computer has hung, restart your computer with an alternate operating system.
2. Search the Dcpromo.exe log to observe if DcPromoSaveDcStateForUpgrade has finished, has succeeded, or has been unsuccessful.
3. Check the Dcpromo.exe log for the run time of DcPromoSaveDcStateForUpgrade.
4. If the upgrade had been initiated with an incorrect RSL size, start Registry Editor (Regedt32), set the RSL directly, and then restart the computer.