How to change the version of Reporting Services 2005 from 64 bits to 32 bits?

Have you ever been in a situation that you installed Reporting Services in a 64 bits machine and then, after a while, you realized that you should have installed the 32 bits version instead?

Or wanted to change from 64 bits version to 32 bits because, suddenly you need to run other applications that are 32 bits version?

Or you Reporting Services 64 bits was working fine for a while and somebody else installed 32 bits and your report manager shows the following message:


Server Error in '/Reports' Application

Attempted to load a 64-bit assembly on a 32-bit platform. Use ReflectionOnlyLoad()

instead if trying to load for reflection purposes.


The cause of this is that you cannot run 32 bits and 64 bits applications simultaneously in the same machine.

Shifting from version of ASP.NET 32 bit to 64 bit can be easy by following the instructions in the article bellow:


How to switch between the 32-bit versions of ASP.NET 1.1 and the 64-bit version of ASP.NET 2.0 on a 64-bit version of Windows;EN-US;894435)


Side-by-side deployment of 64-bit and 32-bit versions is not supported and there is no way to change Reporting Services version from 32 to 64 or vice versa. You would have to uninstall one version and install the other.


Note that there is no need to uninstall SQL Server 2005, just Reporting Services 2005 (RS 2005 is a component of SQL 2005). This is good because sometimes we cannot afford to uninstall SQL Server 2005 and we can just deal with Reporting Services individually.


Uninstalling Reporting Services 64 bits version after installing 32 bits could be a bit tricky. You would have to follow the steps:

1.       If you already have reports created, you would need to backup the databases and the encryption keys in order to restore the data back when you install the new version. You have more info in the article bellow.

How to move a Reporting Services database from a computer that is running Reporting Services to another computer

1.       Configure IIS to run in mode 64 bits, Otherwise, you won´t be allowed to uninstall Reporting Services (64):

Open a command prompt window, and then run the following command:

cscript %SystemDrive%\inetpub\AdminScripts\adsutil.vbs set w3svc/AppPools/Enable32bitAppOnWin64 0

2.       Uninstall Reporting Services by choosing the option “Change” from “Add Remove Programs”

3.       Make sure that the virtual folders Reports and ReportServer dont exist in IIS (If they do, remove them manually)

4.       If the databases still exist in Management Studio, you have two options: if you want a new installation and not keeping your old reports and configuration, I would advise you to remove them. If you want to keep the old reports and configuration, leave them and reconnect later.

5.       (OPTIONAL) If .NET framework isn´t installed already, you would do it by:

a.     Run dotnetfx64.exe to install the .NET Framework manually. You can find this file in the Redist folder on the SQL Server Setup media.

b.     In IIS Manager, click the Web Server Extensions folder.

c.     In the Details pane, right-click ASP.NET V2.0.50727, and then click Allowed.

d.     Right-click the Web Sites folder and then select Properties.

e.     Click ISAPI Filters.

f.      In Filter Name, select ASP.NET_2.0.50727, and then click Edit.

g.     Replace "C:\WINDOWS\Microsoft.NET\Framework64\v2.0.50727\aspnet_filter.dll" with the 32-bit version that is located in the Framework folder: C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\aspnet_filter.dll

6.       Configure IIS to run in 32 bits mode and register aspnet 32 bits:

Open a command prompt window, and then run the following command:

cscript %SystemDrive%\inetpub\AdminScripts\adsutil.vbs set w3svc/AppPools/Enable32bitAppOnWin64 1

To register aspnet run the following command:

%SYSTEMROOT%\Microsoft.NET\Framework\v1.1.4322\aspnet_regiis.exe -i

7.       Restart IIS by running the command:


8.       Install Reporting Services (32 bits)

9.       Install Service Pack 2 of SQL Server 32 bits (only the Reporting Services component will be checked and installed as the version of SQL Server is 64 bits)

10.   Restore the encryption keys previously backed up


Maria Esteban

Ingeniero de Soporte de Reporting Services

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