Service Pack 2 for Windows 2000 adds native compatibility mode support to the OS, letting you install or run programs by "tricking" them into thinking that the OS is either NT or 95.
Here is an excerpt from the Microsoft Knowledge Base article found at:
http://support.microsoft.com/support/kb ... 9/7/92.asp
SUMMARY
Compatibility mode provides an environment for running programs that more closely reflects the behavior of either Microsoft Windows 95 or Microsoft Windows NT 4.0. These modes resolve several of the most common issues that prohibit older programs from working correctly with Windows 2000. Programs that experience issues after migration may benefit from being started in one of these compatibility environments.
The Compatibility-mode technology is currently used by Windows 2000 to ensure built-in compatibility for many popular programs. With Windows 2000 Service Pack 2 (SP2), administrators can manually enable and use this technology to provide solutions for their own programs. Only administrators can enable this technology for users.
HOW TO ENABLE COMPATIBILITY MODE PROPERTIES
The Compatibility-mode technology is not exposed by default. To enable an interface so that you can use this technology for your programs after you apply SP2: Log on as Administrator.
Click Start, and then click Run.
In the Open box, type the following command, and then click OK, where %SystemRoot% is the drive and folder in which Windows 2000 is installed:
regsvr32 %systemroot%\apppatch\slayerui.dll
HOW TO USE COMPATIBILITY MODE PROPERTIES
Administrators can use a program shortcut to set the compatibility mode for a target program. This requires that the Compatibility-mode properties be correctly installed and registered on the computer by using the previous steps. To enable Compatibility mode by using a program shortcut: Log on as Administrator.
Right-click the shortcut, and then click Properties.
Click the Compatibility tab. This tab appears only if the Compatibility-mode interface has been properly enabled on the computer.
Click to select the Run in Compatibility Mode check box to enable Compatibility-mode support for the program.
Click either Windows 95 or Windows NT 4.0 compatibility mode in the drop-down box.
Click OK to save the changes.
Double-click the shortcut to run the program.
NOTE: Be careful if you use Compatibility mode to bypass version warnings in Setup or installation programs. Some programs are designed for a specific operating system and intentionally prohibit use on future versions. These are most often system-level programs that run at a very low level and have the potential to cause serious problems if installed.
HOW TO DISABLE COMPATIBILITY MODE
Because you enable Compatibility mode independent of the Windows 2000 Service Pack 2 installation process, uninstalling Windows 2000 Service Pack 2 does not remove Compatibility mode. To uninstall Compatibility mode: Log on as Administrator.
Click Start, and then click Run.
In the Open box, type the following command, and then click OK, where %SystemRoot% is the drive and folder in which Windows 2000 is installed:
regsvr32 /u %systemroot%\apppatch\slayerui.dll
Enable compatibility mode in Windows 2000 SP2.
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