When installing SQL Server 2011 Denal , you might get the following error, if you are installing on Windows XP operating System , because Windows XP is not supported for SQL Server 2011.
The operating System on this computer does not meet the minimum requirements for SQL SERVER "Denali".For more information, see Hardware and Software Requirements for installing SQL SERVER at http://go.microsoft.com/fwlink/?LinkID=195092
Microsoft SQL Server 2011 Requirements
During Microsoft SQL Server 2011 installation, in order to install SQL Server 2011 without a problem and an interruption please take care to the Microsoft SQL Server 2011 Requirements list. It is better to install the Microsoft SQL Server 2011 requirements before starting
The operating system requirements for Microsoft SQL Server 2011 are as follows.
Microsoft SQL Server 2011 aka SQL Server Denali CTP 1 Evaluation version supports:
Windows Vista with SP2,
Windows Server 2008 with SP2,
Windows 2008 R2, and
Windows 7 operating systems.
What is interesting related with the supported operating systems list is Windows XP is not supported any more.
I have successfully installed MS SQL Server 2008 R2 on my Windows XP machine; SQL Server 2011 Denali CTP 1 cannot be installed.