Most modern software (even legacy versions of browsers) won't even launch without SP1 detected. How to Tell If You Have It
You need approximately 1.5 GB of free space for the installation.
If you manage systems containing this GUID, your next step should be to validate its origin against your change management database. If the origin is unknown, replace the system or reinstall from known-good Microsoft media (MSDN, Volume Licensing Service Center, or original OEM SP1 ISO).
Still Rocking Windows 7? Here’s Why SP1 (x64) is Non-Negotiable
b78b8e95-9e46-4f7a-9d1d-f64477bb7326 . File Size: Approximately 912.4 MB.
Windows 7 Service Pack 1 for x64-based Systems. Knowledge Base ID: [KB976932](microsoft.com. Update ID: b78b8e95-9e46-4f7a-9d1d-f64477bb7326 . Release Date: May 31, 2011. Architecture: x64 (64-bit). File Size: Approximately 912.4 MB. Core Functionality
The string you provided is the specific for Windows 7 Service Pack 1 (SP1) for x64-based Systems (KB976932) .
You’ll need approximately 1.5 GB of free space for the standalone installer.