http://blog.csdn.net/wochuailimin/article/details/6120462
Http://www.cnblogs.com/huangcong/archive/2010/03/30/1700348.html
Installing SQL 2005 Warning 32-bit ASP. NET already registered, need to register 64 bit ... Solution Solutions
You can run the following two commands:
1. Register 64-bit. NET on IIS.
cscript C:\inetpub\adminscripts\adsutil.vbs SET W3svc/apppools/enable32bitapponwin64 0
And
C:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\aspnet_regiis.exe-i
2. Register 32-bit. NET:
No need to uninstall 32 bits, the registration command is the above command. The system is installed by default on 64-bit systems, but since most of the client programs are developed under 32-bit. NET, IIS's. NET is registered as a 32-bit version by default, making it easy for customers to use. If you run the above command after the installation is successful, you need to run
cscript C:\inetpub\adminscripts\adsutil.vbs SET W3svc/apppools/enable32bitapponwin64 1
And
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis.exe-i
Re-register 32-bit. NET in IIS to prevent 32-bit programs from running under 64-bit. NET. The default environment can be successfully installed.
SQL 2005 Installation