We strongly recommend you to install the latest Microsoft Service Packs and updates. Microsoft Service Packs fix a lot of bugs and problems of the operation system and add some new features to the system.
"Download Windows Service Pack to obtain updates that can help improve security, application compatibility, operating system reliability, and Setup."
You can install Service Packs automatically from Windows Update service or install it manually from the official site of Microsoft:
Microsoft Download Center: Windows
Windows Vista Service Pack 1 Five Language Standalone (KB936330) 434.5 MB
Windows Vista Service Pack 1 Five Language Standalone for x64-based Systems (KB936330) 726.5 MB
Release Notes for Windows Vista Service Pack 1 (v3.2, 3/18/2008)
Note: Use the latest version of Service Pack only! Do not install the previous versions.
Using WinTools.net you can get the information(from the first page of the program) about what version of Windows
7/Vista you have installed and what Service Pack was applied:
As you see on Screen Shot - Windows Vista Ultimate with Service Pack 1 was installed on a PC.
Service Packs 1 contain useful vsp1cln.exe utility. The official Microsoft information about the utility:
"Windows Vista SP1 File Removal tool (Vsp1cln.exe). Vsp1cln.exe is an optional tool that you can run after you install SP1. This tool removes older versions of components that have been updated in SP1, which are stored during the installation in case you need to uninstall SP1 later. Saving these older components increases the amount of disk space that is used. Typically, you should run Vsp1cln.exe if you want to reclaim this disk space after applying SP1 and if you will not need to uninstall SP1. Note, however, that you cannot uninstall SP1 after you run this tool. You can use this tool both online and offline, but you must have SP1 installed and you must use the correct version of the tool. If you are running this file on an offline image, you should use the Vsp1cln.exe included in the Windows OPK or AIK. However, if you are running this file online (on a computer that you are booted into), you should use the Vsp1cln.exe file
located at %windir%\system32\vsp1cln.exe."
You can free the Hard Disk space removing the old system files using vsp1cln.exe utility. For that close all the applications on your Desktop, run WinTools.net and select Command Prompt... point of menu:
In Command Prompt window type vsp1cln.exe and press Enter:
Press Y to continue process.