We are trying to do an in-place upgrade from SQL 2005 express to workgroup
edition. As it is an upgrade we use the command line “setup SKUUPGRADE=1�
every thing runs OK but when installing the packages next error appear
“Product: Microsoft SQL Server 2005 Backward compatibility -- Error 1706. An
installation package for the product Microsoft SQL Server 2005 Backward
compatibility cannot be found. Try the installation again using a valid copy
of the installation package 'sqlserver2005_bc.msi'.�

Below is the summary offered by the installer after the error

Thanks in advance

Microsoft SQL Server 2005 9.00.2047.00
==============================
OS Version : Microsoft Windows XP Professional Service Pack 2 (Build
2600)
Time : Fri Apr 20 15:28:17 2007

Machine : IOTSERVER
Product : Microsoft SQL Server Setup Support Files (English)
Product Version : 9.00.1399.06
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SQLSupp ort_1.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server Native Client
Product Version : 9.00.2047.00
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SQLNCLI _1.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft Office 2003 Web Components
Product Version : 11.0.6558.0
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_OWC11_1 .log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : SQL Server Backward-Compatibility Files
Error : An installation package for the product Microsoft SQL
Server 2005 Backward compatibility cannot be found. Try the installation
again using a valid copy of the installation package 'sqlserver2005_bc.msi'.
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server 2005 Backward compatibility
Product Version : 8.05.1704
Install : Failed
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_Backwar dsCompat_1.log
Last Action : InstallFinalize
Error String : An installation package for the product Microsoft SQL
Server 2005 Backward compatibility cannot be found. Try the installation
again using a valid copy of the installation package 'sqlserver2005_bc.msi'.
Error Number : 1706
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : MSXML 6.0 Parser (KB927977)
Product Version : 6.00.3890.0
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_MSXML6_ 1.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server Setup Support Files (English)
Product Version : 9.00.1399.06
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SQLSupp ort_2.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft Office 2003 Web Components
Product Version : 11.0.6558.0
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_OWC11_2 .log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server Setup Support Files (English)
Product Version : 9.00.1399.06
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SQLSupp ort_3.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server Native Client
Product Version : 9.00.2047.00
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SQLNCLI _2.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft Office 2003 Web Components
Product Version : 11.0.6558.0
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_OWC11_3 .log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : Microsoft SQL Server VSS Writer
Product Version : 9.00.2047.00
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_SqlWrit er_1.log
--------------------------------------------------------------------------------
Machine : IOTSERVER
Product : MSXML 6.0 Parser (KB927977)
Product Version : 6.00.3890.0
Install : Successful
Log File : c:\Archivos de programa\Microsoft SQL Server\90\Setup
Bootstrap\LOG\Files\SQLSetup0011_IOTSERVER_MSXML6_ 2.log
--------------------------------------------------------------------------------