Late last year Microsoft revealed that Visual Studio 2005 would not work on Windows Vista when it was released. About a month after Vista’s release, Mary Jo Foley reported that Microsoft had released a patch for VS 2005 that would make it compatible with Vista. It’s available here. They’re calling it “Visual Studio 2005 Service Pack 1 Update for Windows Vista”. This is not SP 1. In fact the download page says in the system requirements that you should only apply this patch to Windows Vista with VS 2005 SP 1 installed on it. It is an update to SP 1, only for Vista. Windows XP users do not need this patch.
Service Pack 1 for VS 2005 is available here. Despite the name you see in the title: “Microsoft Visual Studio 2005 Team Suite Service Pack 1”, this is SP 1 for all commercial editions of VS 2005.
They’ve made a version of Service Pack 1 for the Express editions of VS 2005 as well, here.
Here’s the information page on VS 2005 SP 1 where information on all editions is covered.