Yesterday, I wasted a few hours trying to upgrade my SQL Server 2005 installation to 2008. Actually, upgrading is a simple process. You can simply select, which instance to upgrade, and the installer does the rest. It worked absolutely fine for my regular instance. I got some installation errors for a component, but didn't mind that at first. Everything seemed to be working.
At least I thought so, until I noticed, WHAT component got the errors. The SQL Server Management Studio was not installed. And the older 2005 version isn't able to connect to 2008. Bummer.
So I thought, let's try to reinstall it. Same error: "The error code is 2349." When you copy the details to the clipboard, you at least find the URL http://www.microsoft.com/products/ee/transform.aspx?ProdName=Microsoft+SQL+Server&EvtSrc=setup.rll&EvtID=50000&ProdVer=10.0.1600.22&EvtType=0xF45F6601%25401201%25401, that gives you the information, that the SQL Server Native Client is causing the trouble.
So I tried upgrading my SQL Server Express instance, but that was also dismissed with an error. Next, I uninstalled my SQL Server 2005 express instance, uninstalled the native client, and now added the Management Studio feature to my SQL Server 2008 instance. Same error, this is really getting frustrating.
So now, my last resort is to uninstall the whole d*rn thing and try to reinstall it. At least the installation only takes about 2 hours *cough*.
UPDATE: Even the complete uninstall did not help. As the error message states, the Native Client is supposedly not installed from the sqlncli.msi package. Well, I even uninstalled and reinstalled ONLY THAT package, to no avail. I'm still getting the same bogus error, when I try to install SSMS. Any help is welcome! I'm out of ideas.
But at least I'm not all alone with my ss2008 install problems. A friend of mine had other issues, but at least he was able to resolve them: http://www.entwicklungsgedanken.de/2009/01/28/installation-problems-with-sql-server-2008/comment-page-1/#comment-252.
UPDATE 2: I have found out, that it's the Visual Studio Tools for Applications 2.0 installer, that is causing the problems. But I still have no idea why.
UPDATE 3: Rollback all rants :-) I found the issue. A file could not be replaced/updated by the installer. This was due to the fact, that my hard disk seems to be defective. The file could not be read, even less replaced. After renaming it, the installation went fine. So now, I have performed a scandisk, the errors have been cleared, and everything is in order. Guess I'll be backing up more often now, though.