Uninstalling SQL Server 2008 November CTP

The November CTP of SQL 2008 has recently been released but unfortunately, my initial attempts at installing it have not been too successful.

After the main database engine failed to install, I was left with an installation that could not be uninstalled through Add/Remove programs. My second attempt resulted in an installation that prevented me from logging on using Windows/SQL authentication and I could not even login from the dedicated admin connection.

Over the past few days, I’ve learned a few things about SQL Setup and here are some notes on performing a manual uninstall. It’s very possible that these suggestions will not work or may even cause further damage – I suggest them only as a last resort before hacking the registry.

When SQL Server setup is executed, several ‘bootstrap’ files are copied into C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap.  These files are required to uninstall SQL and if you’ve deleted them, you’ll need to replace them. One possibility is to run setup on a different machine and to copy the files back over.

In the bootstrap folder, you’ll find a copy of ARPWrapper.exe. The link to uninstall SQL from Add/Remove programs makes a call to ARPWrapper and removal will fail if the reference to this has been lost. Therefore, a possible suggestion is to open a command prompt, go to C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap (or wherever you’ve installed SQL) and type in the following command:

ARPWrapper.exe /Remove

If this fails, the documented approach from the readme file is to uninstall each component one by one. Again, open a command prompt, go to the bootstrap folder and run the following commands:

To remove the SQL Engine:
Setup100.exe /Action=uninstall /SQLInstanceID=<Instance ID for the Database Engine>/Features=SQL

To remove Analysis Services:
Setup100.exe /Action=uninstall /ASInstanceID=<Instance ID for Analysis Services>/Features=AS

To remove Reporting Services:
Setup100.exe /Action=uninstall /RSInstanceID=<Instance ID for Reporting Services>/Features=RS

If SQL Server 2008 was installed as the default instance, the Instance ID will be MSSQLSERVER. Make sure that Setup100 exists on a local drive. If it is run from a mapped a network drive, it is likely to fail with a security exception.

A third option for un-installation is to call the msiexec utility with the /x parameter. In the registry, the SQL 2008 components can be found beneath HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall in a folder identified by a GUID. At a command prompt, type in the following command substituting the GUID that appears in the registry:

msiexec /x {GUID}

On a more positive note, I finally installed the CTP on a fresh VPC. This time round, the install routine was slick and seamlessly included the installation of the .Net Framework v2. Cosmetically, the Setup screen looks different and includes an ‘Installation Centre’. Within the install wizard, the items appear along the left hand pane and notice how the validation errors appear in a dropdown across the top.

The SQL Server 2008 Installation Centre

 
Part of the SQL Server Install Wizard with validation errors highlighted

The November CTP is great once it’s installed. For anyone experiencing installation problems, I strongly recommend downloading the VHD instead or flattening your VPC before spending too much time on fixing the problem like I did.