by  AGILEIT\john  on 3/4/2008 9:28 AM

I had issues uninstalling the 32 bit SQL 2005 Express and SQL 2005 Standard from a customers machine running Windows 2003 64bit.   This was due to Systems Center Essentials requirement of having a 64 bit SQL when running on a 64 bit box with registry redirection.

The server ha two previous versions of the 32 bit reporting services (SQL and SQL Express)...and even after a complete uninstall, I could not reinstall SQL 2005 x64 bit and have function properly.  I received errors after the 64 bit install on the Configuration Tools > Reporting Services Configuration (WMI Error 80040219).  Also, when connecting to the reporting instance through SQL 2005 Management Studio (Could not complete operation, WinMgmt). When I tried to reinstall SQL using the default instance, I received an error that the default instance was installed, even when I removed everything (add/remove programs, SQL services, program files).

So, even after I thought I had removed all of the 32 bit SQL services on the machine, I kept having errors with 64 bit reporting services not being able to be configured. It was because the instance name still existed in the redirected 32 bit node of the registry (WOW6432node)

The quick fix to this problem was to delete the old 32 bit SQL configuration that was preventing the 64 bit version of reporting services from working from:

HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432node\Microsoft\Microsoft SQL Server

Note - That will destroy any 32 bit SQL running on your 64 bit box...please make sure the services are deleted as detailed below.

Uninstalling SQL 2005 Manually

First, here are the recommended steps to manually uninstall SQL 2005:

http://support.microsoft.com/kb/909967

If that doesn't work, this is how you can manually uninstall all versions of SQL 2005 so that SQL can be reinstalled: .

Note - This method will delete all databases and configuration, you must have a backup of your existing SQL databases (which this uninstall will delete) before proceeding. (Again, this is not supported, please call Microsoft PSS for supported methods)

1. Uninstall all SQL components possible in Add/Remove Programs (including the SQL client and VSS writer)
2. Stop all SQL Services and configure them to disabled using Start > SQL Configuration Manager
3. Delete the following registry to get rid of the services.  If you have multiple instance installed, it will be Keyname$Instance (i.e. MSSQLServer$OFFICESERVERS)
   1. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSSQLServer
   2. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SQLServerAgent
   3. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSSQLServerADHelper
   4. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ReportServer
   5. Verify that the services do not exist in the SQL Configuration Manager.
4. Delete the SQL Configuration in the registry
   1. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer
   2. HKEY_LOCAL_MACHINE\Software\Microsoft\Microsoft SQL Server
   3. Note - if you installed a 32 bit version of SQL on 64 bit version of Windows, you will need to also delete them from the 32 bit registry node that is redirected. More Info MS 896459.
      * HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432node\Microsoft\MSSQLServer
      * HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432node\Microsoft\Microsoft SQL Server
5. Delete the SQL Program files - Note this will also delete the existing databases on the system that must be restored from backup.
   1. Delete the directory: C:\Program Files\Microsoft SQL Server
      Note - if you installed a 32 bit version of SQL on 64 bit version of Windows, you will need to also delete them from the 32 bit program files:
      C:\Program Files (x86)\Microsoft SQL Server
   2. You might need to reboot to close all files before you can delete the directory.

Now you can reinstall a clean 32 bit or 64 bit SQL without errors.