Today I upgraded to the just released Visual Studio 2008 Service Pack 1 and as I was using various beta versions of the Service Pack and of the Silverlight SDK together with Visual Studio, I thought I should write down my installation experiences. First, any beta versions of the "Visual Studio 2008 Service Pack 1" should be manually removed from the system. I also suggest, uninstalling the June edition of the "Silverlight 2 Beta 2 Tools for Visual Studio 2008", the "Silverlight 2 Beta 2 SDK" and the "Silverlight 2 Beta 2 Runtime". Don't worry, we will re-install the latest versions of all of these components again later. Now, download and run the "Visual Studio 2008 Service Pack 1 Preparation Tool". It will take care of removing any hotfixes that may not be compatible with Visual Studio 2008. This tool would also have uninstalled the items mentioned above, but I preferred to do that manually. Make sure to have the original Visual Studio 2008 installation media ready as it may be required during the clean-up process. This is a good point to get some coffee. The preparation tool takes quite a while to run.