Microsoft has released Windows Vista Service Pack 1 RC1. The All-Language standalone package (32-bit / 64-bit) supports installations on all versions of Windows Vista with one or a combination of the 36 Windows Vista languages installed. If you already installed the Service Pack to your machine by using the standalone package, you must uninstall before you scan Windows Update for Windows Vista SP1.  Systems running on Windows Vista RTM require as many as three updates before SP1 can be installed. These updates are permanent to your Windows Vista systems. Windows Update will detect your system configuration and offer the prerequisite packages that are applicable to your system. Here are 4 simple steps to get SP1 on your machine.

On Vista RTM:
1. Download the self extracting executable and extract its contents to a folder on your computer. Run the script on an elevated prompt.
- To run the script on elevated prompt, after you download the script, right click on the file and select "Run as administrator" option.
- The script sets a registry key on your system. The registry key is required for WU server to recognize your machine as a valid target for Vista SP1.
- After running the script, Windows Update automatic updates would normally automatically update your machine each night for the next several days with the prerequisites and then offer the Service Pack. However if you would like to install SP1 quicker you can manually do the next few steps to speed up the process.

2. Install all pending "Important" updates and reboot. You may have to do this several times to get fully up to date.
- Check for updates on Windows Update. Go to Control Panel à System and Maintenance à Windows Update and check for updates by clicking on "Check for Updates" in the top left of the task pane.
- You will be offered all previously released Windows Vista updates that you may not have installed on your system. Install all applicable updates. If you have a clean install of RTM, there might be quite a few updates to install. You may need to do this a couple of times to get fully up to date. At some point Update for Windows (KB935509) will be in this list. This is the first pre-requisite install. Reboot your machine when prompted.
- If you see Ultimate Extras, you can hide them by right-clicking and hiding. Simply unchecking them will not let the remaining updates show up. Please install all of the remaining "important" updates.
- If you reboot and rescan right away, at times you may not see all updates right away. Wait 10 minutes and scan again.

3. Install Update for Windows (KB937287) and Update for Windows (KB938371) as they are offered sequentially
- The first package that will be offered is Update for Windows (KB937287) and it does not require a reboot.
- Check for updates on Windows Update again, install and reboot when prompted for Update for Windows (KB938371). You may need to wait 10 minutes and re-scan again if it does not show up right after reboot.

4. Install Windows Vista Service Pack 1 (KB936330).
- Check for updates on Windows Update again, install and reboot when prompted for Windows Vista Service Pack 1. You may need to wait 10 minutes and re-scan again if the package does not show up right after the previous reboot.
- This process will typically take from 30 minutes to 1 hour but may take longer on some systems."