SQL Server 2008 R2 installation fails

Installation wizard says 2005 tools should be uninstalled even after uninstalling all 2005 components

This is due to some add-ons installed for SQL Server 2005.

Here is the solution I found somewhere I don't remember: (Thanks to the author and I am sharing further)

1. run Regedit

2. Check HKLM\SOFTWARE\Microsoft\Microsoft SQL Server\90\Tools\ShellSEM
3. If it exists, rename "ShellSEM" to anything

4. Run SQL server 2008 installation again