Running 32 bit .net application on 64 bit operating system

IIS 6.0 supports both the 32-bit mode and the 64-bit mode. However IIS 6.0 does not support running both modes at the same time on a 64-bit version of Windows. ASP.NET 1.1 runs only in 32-bit mode. ASP.NET 2.0 runs in 32-bit mode or in 64-bit mode. Therefore, if you want to run ASP.NET 1.1 and ASP.NET 2.0 at the same time, you must run IIS in 32-bit mode.


ASP.NET 1.1, 32-bit version
To run the 32-bit version of ASP.NET 1.1, follow these steps:
1. Click Start, click Run, type cmd, and then click OK.
2. Type the following command to enable the 32-bit mode:
cscript %SYSTEMDRIVE%\inetpub\adminscripts\adsutil.vbs SET W3SVC/AppPools/Enable32bitAppOnWin64 1
3. Type the following command to install the version of ASP.NET 1.1 and to install the script maps at the IIS root and under:
%SYSTEMROOT%\Microsoft.NET\Framework\v1.1.4322\aspnet_regiis.exe -i
4. Make sure that the status of ASP.NET version 1.1.4322 is set to Allowed in the Web service extension list in Internet Information Services Manager.


ASP.NET 2.0, 32-bit version
To run the 32-bit version of ASP.NET 2.0, follow these steps:1. Click Start, click Run, type cmd, and then click OK.
2. Type the following command to enable the 32-bit mode:
cscript %SYSTEMDRIVE%\inetpub\adminscripts\adsutil.vbs SET W3SVC/AppPools/Enable32bitAppOnWin64 1
3. Type the following command to install the version of ASP.NET 2.0 (32-bit) and to install the script maps at the IIS root and under:
%SYSTEMROOT%\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis.exe -i
4. Make sure that the status of ASP.NET version 2.0.50727 (32-bit) is set to Allowed in the Web service extension list in Internet Information Services Manager.


ASP.NET 2.0, 64-bit version
To run the 64-bit version of ASP.NET 2.0, follow these steps:1. Click Start, click Run, type cmd, and then click OK.
2. Type the following command to disable the 32-bit mode:
cscript %SYSTEMDRIVE%\inetpub\adminscripts\adsutil.vbs SET W3SVC/AppPools/Enable32bitAppOnWin64 0
3. Type the following command to install the version of ASP.NET 2.0 and to install the script maps at the IIS root and under:
%SYSTEMROOT%\Microsoft.NET\Framework64\v2.0.50727\aspnet_regiis.exe -i
4. Make sure that the status of ASP.NET version 2.0.50727 is set to Allowed in the Web service extension list in Internet Information Services Manager.
Note The build version of ASP.NET 2.0 may differ depending on what the currently released build version is. These steps are for build version 2.0.50727.