SQL server 2008 installation error

installationsqlsql-server-2008sql-server-express

I had installed trial version of SQL 2008 R2 on my machine with win 7 as OS. Today I uninstalled it since trial expired then I tried to install SQL 2008 express edition with Advanced services but I keep getting below error:

SQL Server Setup has encountered the following error Method not found Boolean Microsoft.SqlServer.Configuration.MsiExtension.MsiExtensionMetadata.get_IsSlipstreamOrPatch()

Best Answer

You have to manually and completely un-install SQL Server first, as per this KB