Windows 2000 Service Pack 4 (SP4) provides the latest updates to the Windows 2000 family of operating systems. These updates are a collection of fixes in the following areas: application compatibility, operating system reliability, security, and setup. Windows 2000 SP4 includes the updates contained in Windows 2000 Service Pack 1 (SP1), Windows 2000 Service Pack 2 (SP2) and Windows 2000 Service Pack 3 (SP3). If you have already installed a previous service pack, download and install SP4 without removing the previous service pack. Microsoft considers Windows 2000 SP4 to be a recommended upgrade – especially if you don’t have either SP1, SP2 or SP3.
If you install SP4 over Windows 2000 Service Pack 1 (SP1) or an earlier release of Windows 2000, your computer will automatically be upgraded to 128-bit encryption to provide better online and local security and to bring your computer up to the current worldwide encryption standard. Beginning with Windows 2000 Service Pack 2 (SP2), 128-bit encryption is supported as the default, so if you previously installed SP2 or Windows 2000 Service Pack 3 (SP3), your computer has already been upgraded to this level of encryption. Important: your computer retains 128-bit encryption even if you revert to Windows 2000 or SP1 unless you reformat your hard drive and complete a new installation of Windows 2000 or Windows 2000 with SP1.
For more information about the fixes in SP4, see the readme that is in the download - it can extracted with a zipping tool.DOWNLOAD Windows 2000 Service Pack 4 (W2K SP4)
