I Found this one out the hard way. I was upgrading a client's website to use Reporting Services so I uninstalled the plain SQL Express 2005 Sp1 to replace it with the Advanced Services package that has Reporting Services in it.

Since I was on a remote server and doing the install via Remote Desktop, when the uninstall of the SQLExpress Sp1 did not ask for a reboot, I proceeded right away to attempt the install of SQLEXPR_ADV.EXE.

You get through the first few screens just fine, then you get to select your installation options. Short pressing "Next >" on the next couple of screens gets you to the actual install and before too long you'll start seeing little-red-X icons popping up in the installer, I think the first to fail in SQL Server Native Client.

At first, I thought it was a failed uninstall because I forgot to explicitly remove the original set of SQL Express support files (MSXML 6.0, Native Client, Management Studio, etc.), among other things. Even trying to uninstall them through Add/Remove programs was producing a vague error message: "Fatal error during installation"... No help at all there.

Several re-attempts later I had a more careful look at the setup log files to try and extract some hint from when I spotted this:

"IsPendingRebootKey. Return value 3."

...So my hunch was that "3" for a return value just isn't a typical value to indicate "everything's OK"-- you'd expect a "1" or a "0" before anything else.

So I crossed my fingers and rebooted the client's server and in four minutes it was back online and I was starting up the install for the fifth time, holding my breath all the way until the installer screen started filling up with many, many green checkmarks icons and I sighed with relief.

What is odd to me is I've had so many Microsoft installs refuse to begin the install wizard if it detects a pending reboot. I could have saved alot of time and worry if I was more skeptical of Windows Installer.

Tags: sql server, remote desktop, installation, errors, reporting services