.SP3 File Extension

File created in the National Geodetic Survey (NGS) Standard Product #3 (SP3) format; saved in a plain text ASCII format and contains satellite orbit information; used for tracking GPS satellite orbits, but also supports non-GPS orbits as well.

The original SP3 format, called SP3-a, was extended to include additional information in the SP3-b and SP3-c formats.

An SP3 file is a data file included in Windows XP Service Pack 3 (SP3). It contains fixes and enhancements that can be applied to a user's copy of Windows XP. SP3 files use the filenames WIN51IP.SP3 and WIN51IC.SP3, and they are similar to .SP and .SP2 files.

Before PCs and operating systems were regularly updated over the Internet, they were updated using physical CD-ROMs. Windows XP updates were stored on Windows XP Service Pack CDs. These CDs contained a number of files and folders, including a data file used to apply fixes and enhancements to a user's copy of Windows XP. On the Windows XP Service Pack 3 disc, that file was named WIN51IP.SP3 (Windows XP SP3 Professional Edition) or WIN51IC.SP3 (Windows XP SP3 Home Edition).

Microsoft released Windows XP Service Pack 3 on April 21, 2008. This final Windows XP Service Pack included features that had first been made available in Windows Vista, additional security improvements, and 1,174 bug fixes.

SP3 files are not meant to be opened. If you still possess a copy of Windows XP Service Pack 3, you can use the disc to apply the fixes and enhancements its SP3 file contains to Windows XP. To do so, insert the disc into your CD-ROM drive, browse to the disc in File Explorer, and double-click SETUP.EXE.