login failed for user (Microsoft SQL Server error: 18456)

So you had some problems with your installation of the SQL Server 2005 installation on your machine and now that you have un-installed and installed it, you can't seem to log on to your own machine using basic windows authentication. You can log into other servers but you just can't seem to log on to localhost. So you search the internet for the error message and after going through a whole lot of issues that are vaguely related, like changing authentication type from windows to sql and so on and so forth, you land on my blog.

The Solution: Install Visual Studio 2005 SP2

This was a bug in SQL Server 2005 that was fixed in SP2.