I had originally installed SQL 2005 Express on my laptop, and something happened during the installation and it got corrupted. I was unable to uninstall, whether I used Add/Remove programs, ran setup.exe ACTION=uninstall from the command line while in the SQL root path, even if I used msicuu2 and msizap to look for the GUIDs associated with SQL 2005. Nothing worked. I thought installing SQL 2008 Express might “fix” or overwrite something and then get me the latest version to play with anyway. Couldn’t have been further from correct. Now I had two corrupt installations and no way to remove either one.
After much research online and trial and error, I was at a point of giving up and wiping the hard disk. I HATE wiping the hard disk for something like this, I feel like I failed somehow. Outside of serious corruption there’s always a way to fix something software related, right? Well, I stumbled upon an MSDN posting later today where users were having similar issues, and one person suggested removing the following registry entry:
HKLMSOFTWAREMicrosoftMicrosoft SQL Server90
So, I went back into Add/Remove Programs, removed all things SQL, stopped all SQL services and set them all to Disabled, restarted the computer, made sure visual Studio 2008 had SP1 installed (because once before it barked at me saying that was required) and tried the install again. Voila! Everything installed perfectly except Full Text Search. Since I’ve been without a local database on my development machine for the past two years, Full Text Search is the least of my problems right now! I’m just thankful I finally have something to work with.
So, if anyone is having problems with the Express SQL versions, or something similar is happening that is preventing you from upgrading to either SQL 2008 Express or SQL 2008 Enterprise or Standard, check out this MSDN thread and see if it helps you: