Microsoft added a compatibility mode to Windows 2000 Service Pack 2 (SP2) that was previously available only in the Microsoft Windows 2000 Server Resource Kit's Application Compatibility Toolkit. This mode is useful if you have an old application that won't run on Win2K. The compatibility mode lets Win2K run as Windows NT 4.0 SP5 or Windows 9x for a selected application.

You need administrative privileges to run Win2K's compatibility mode. To enable the mode, go to a command prompt and enter

regsvr32 %systemroot%apppatch\slayerui.dll

After you enable the mode, each time you view a program shortcut's properties you'll see a Compatibility tab. This tab lets you select the compatibility mode you want. You can have several shortcuts to a program, with each shortcut running the program in a different compatibility mode. To disable the compatibility mode, open a command prompt and enter

regsvr32 /u %systemroot%  apppatch\slayerui.dll

Win2K's compatibility mode works only for shortcuts to programs—not to executable files. For more information about the compatibility mode, see the Microsoft article "HOW TO: Enable Application Compatibility-Mode Technology in Windows 2000 SP2 and SP3" (http://support.microsoft.com/?kbid=279792).