Although Windows Vista Service Packs 1 comes with the easy to use system to update its operating system. Beginners are not aware of this. Many of my friends still ask because they are afraid that it may damage their OS.
So here's How to install Sp1:
Method 1: Microsoft recommends using Windows Update to download and install Windows Vista SP1 on single PCs because of driver issues.
1. Download the Standalone File from Microsoft, here
2. Check first if you have a disk space available (A minimum of 7 GB free disk space for 32-bit systems and 12GB for 64-bit computers). Laptops must be plugged in to an AC power source.
4. Now, You're ready, just open the file and proceed with the installation.
5. Save you're work, Close all open programs and then click the Install button. It will take an hour or more... Enjoy!