Since it is a 7-Zip archive, you will need an extractor like 7-Zip or PeaZip .
Archives for older systems like Windows NT 4.0 , Windows 2000 , or Windows 7 often use the .7z extension to store original Service Pack installers. SP1.7z
How to Download and Install Service Pack 1 for Windows 7 (Tutorial) Since it is a 7-Zip archive, you will
System administrators often extract these archives using tools like 7-Zip to "slipstream" (integrate) the Service Pack directly into an OS installation image. How to Handle the File Since it is a 7-Zip archive