Windows VISTA SP1- Pre-Install Checkings

Here is a check-list of some things which you may want to ensure before going ahead with its download and install.
1. Foremost, make sure that you have sufficient Disk Space.
If you plan to use Windows Update, you will need at around 1.2 GB for the 32-bit version, and around 1.5GB for the 64-bit version.
If you plan to download the stand-alone installer package, depending on your Vista version, you will need from 2.5 to 5.5GB for the 32-bit version, and around 4 GB to 8GB for the 64-bit version.
So run Disk Cleanup Utility or freeware CCleaner. If you still feel you are short, think of moving your Songs or Videos or Photographs to another drive or to an external medium. If you try to install SP1, and it finds that available disk space is less, then, the installation process will automatically frsee disk space by removing all existing system restore points and by creating a single new system restore point instead.
2. Best to Run Chkdsk and check your system hard disk for errors.
3. If you have a prior version of the SP1 beta installed, you must uninstall it. It may show as Service Pack for Microsoft Windows KB936330, in your Add Remove Programs. Do note that Windows Update will not offer you Vista SP1, for at least an hour or so, until and after you have uninstalled such a pre-release version.
4. If you have your Automatic Updates enabled, you should have no issues. Nevertheless, check the Updates history and ensure that the following updates show as Installed Successfully and NOT as failed. These are pre-requisites required for Vista SP1.
KB935509. This is only required on Windows Vista Enterprise and Windows Vista Ultimate editions. which have Bitlocker capabilities. This update is required prior to installing KB938371, the 2nd prerequisite package, and is required to prevent potential loss of data on Bitlocker encrypted systems during servicing. KB938371. This package consists of fixes for several components, including the TrustedInstaller, that increases the success rate for installing the service pack, and which enable the service pack to be successfully uninstalled. This must be installed prior to the service pack install itself to enable these fixes. KB937287. This is an update to the “Servicing Stack” or the Windows Vista component installer technologies built into Windows Vista. This update enables the built-in installer to properly and successfully install the service pack itself.
5. Back up your files to an external medium like DVD, CD, USB flash drive, etc. No harm in creating your own system restore point too, manually.
6. Disable your 3rd Party Firewall and Anti Virus.
7. Make sure you are plugged in, to your Mains, when you are downloading and installing the Vista SP1.
8. Check which of your applications may give you a problem post-SP1 install. Best to uninstall them then.

Everthing should go smoothly, but it always good to take a few precautions !