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How to force Asp.net development server to run as a 32-bit process?

I am having problem getting the MS Visual Studio Remote Debugger to connect to my local IE instance as it is running as a 64-bit rather than a 32-bit process.
Every time I try to run it currently in Visual Studio I get the
The 32-bit version of the Visual Studio Remote Debugging Monitor (MSVSMON.EXE) cannot be used to debug 64-bit processes or 64-bit dumps".
error.
Investigating a bit, I think I have narrowed it down to the web asp service being run as a x64 process rather than a x86 (which both Visual Studio, and the silver light application are running as). I confirmed it as running as a 64-bit process by trying to "attach" visual studio to the process when the application was running in the ASP.Net Development Server.
In short: Is there a setting I am missing somewhere to force Visual Studio to run the ASP.Net service as a 32-bit process? I have read about using a variable in the web.config application pool to use 32-bit (via the enable32BitAppOnWin64 config option), but it seems to only work in IIS, not ASP.net Dev server.
Any thoughts?
Edit For Clarity:
I am running Windows 7 64-bit, Visual Studio 2010 (which is running as a 32-bit process). Currently it is launching ASP.NET Development Server (not IIS) to host the back end web service. I am hoping I can simply "fix" this via a setting, but if not my backup would be to run IIS Express.

If I'm understanding you correctly you should do this:
IIS Manager/Application Pools-> choose the correct pool for your application/Advanced Settings/Enable 32-Bit Applications->set it to true !
I had problem like this in the past which cost me 1-2 days, hope this helps !
Check also Project/Properties/Build/Platform target->this should be Any CPU

The 'MSDAORA.1' provider is not registered on the local machine

I have an application that connects to a DB, extracts info, creates a excel file, and then drops the file/emails X people the file.
The application was created in Visual Studios using .NET 2.0 Framework (Windows Form App). It was run on a 32 bit server. But it recently was moved to a 64 bit server. It is now returning with the error message " The 'MSDAORA.1' provider is not registered on the local machine."
I believe that MSDAORA is only supported for 32-bit applications and the Application Pool the app runs under in IIS is not enabled for 32-bit applications.
How would I fix this issue, is there something I can change in IIS? Or is it a code change?

Using ORAOLEDB.ORACLE rather than MSDAORA fixed the same issue for me - changing the platform target from 'Any CPU' to 'X86' caused errors within my project in Visual Studio.
See answer here

I figured out the solutions for this. The problem stemmed from running the machine on a 64bit machine. To change that in VS, open up the properties page of the solution and in the build tab change the targeted platform to x86. And that did the trick.
http://lostechies.com/gabrielschenker/2009/10/21/force-net-application-to-run-in-32bit-process-on-64bit-os/
Thanks for your help Yuriy.

I had the same issue, but I used another solution because my application is running in IIS.
In the advanced settings of the application pool I changed the value for Enable 32-Bit Applications to true.

I had he same issue but it wasn't 32/64bit. I used the ODAC xcopy installer and forgot to run it in a cmd.exe as administrator. It didn't give any error so I had a hard time figuring this out. The xcopy part worked but the DLL registration via regsvr32 silently failed.

https://learn.microsoft.com/en-us/sql/ado/guide/appendixes/microsoft-ole-db-provider-for-oracle?view=sql-server-ver15
11/08/2018
This feature will be removed in a future version of Windows. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. Instead, use Oracle's OLE DB provider.
so probably using ORAOLEDB.ORACLE is the correct solution, but that seems like more effort than just changing the connection string.

Microsoft.ACE.OLEDB.12.0 Provider is not registered on the Local Machine?

I am getting this error when i am trying to install VS project in a 64 bit System. I already download and install AccessDatabaseEngine . There is any other method to do that, i am using MS Access(Office 2007) database to my application. both systems are using x32 system tools **. if i am installing **AccessDatabaseEngine(x64) it is getting an error your system consists of (x32 system tools)

Try to find out your solution from here
For Web
If you have installed the AccessDataEngine and are still getting the Not Registered error
AND
you are running IIS7 on a 64 bit server,
MAKE SURE
you have enabled 32-bit applications for the application pool associated with the website. In IIS, Right click on the application pool. In the properties window, the 2nd option from the top is "Enable 32-Bit Applications". Set it to true.

Bridge between 64-bit and 32-bit application

What would be the best (easiest and fastest) way to provide an access between 64-bit application (ASP.NET) and 32-bit assembly (.NET 32-bit database driver).
1) I've got complete control over this two pieces of code (64-bit and 32-bit),
2) They both run on the same machine,
3) Security is not an issue,
4) Performance is important.

Run the ASP.NET application processes in 32-bit mode. This is the only way to get it to work.
For example, Crystal Reports XI does not have a 64-bit driver. In order to run the report, you must run the ASP.NET app in 32-bit mode on a 64-bit server.
On IIS 6.0:
Click Start, click Run, type cmd, and
then click OK.
Type the following command to enable
the 32-bit mode:
cscript %SYSTEMDRIVE%\inetpub\adminscripts\adsutil.vbs SET W3SVC/AppPools Enable32bitAppOnWin64 1
Now since the IIS worker process is
running in 32 bit mode we need to
ensure the ASP.NET ISAPI filter is
also changed to the 32 bit version.
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
In IIS 7.0, you can set the 32 or 64-bit per application pool whereas on IIS 6.0 it's the entire processes of the server.

I get a "An attempt was made to load a program with an incorrect format" error on a SQL Server replication project

The exact error is as follows
Could not load file or assembly 'Microsoft.SqlServer.Replication,
Version=9.0.242.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91'
or one of its dependencies. An attempt was made to load a program with
an incorrect format.
I've recently started working on this project again after a two month move to another project. It worked perfectly before, and I've double checked all the references.

The answer by baldy below is correct, but you may also need to enable 32-bit applications in your AppPool.
Source: http://www.alexjamesbrown.com/uncategorized/could-not-load-file-or-assembly-chilkatdotnet2-or-one-of-its-dependencies-an-attempt-was-made-to-load-a-program-with-an-incorrect-format/
Whilst setting up an application to run on my local machine (running Vista 64bit) I encountered this error:
Could not load file or assembly ChilkatDotNet2 or one of its
dependencies. An attempt was made to load a program with an incorrect
format.
Obviously, the application uses ChilKat components, but it would seem that the version we are using, is only the 32bit version.
To resolve this error, I set my app pool in IIS to allow 32bit applications.
Open up IIS Manager, right click on the app pool, and select Advanced Settings (See below)
Then set "Enable 32-bit Applications" to True.
All done!

I've found the solution. I've recently upgraded my machine to Windows 2008 Server 64-bit. The SqlServer.Replication namespace was written for 32-bit platforms. All I needed to do to get it running again was to set the Target Platform in the Project Build Properties to X86.

Change the value for Platform Target on your web project's property page to Any CPU.

Go to IIS
-> Application Pool -> Advance Settings -> Enable 32-bit Applications

We recently had the issue when trying to run the code from Visual Studio. In that case you need to do
TOOLS > OPTIONS > Projects and Solutions > WEB PROJECTS and check the "Use the 64 bit version of IIS Express for web sites and projects".

For those who get this error in an ASP.NET MVC 3 project, within Visual Studio itself:
In an ASP.NET MVC 3 app I'm working on, I tried adding a reference to Microsoft.SqlServer.BatchParser to a project to resolve a problem where it was missing on a deployment server. (Our app uses SMO; the correct fix was to install SQL Server Native Client and a couple other things on the deployment server.)
Even after I removed the reference to BatchParser, I kept getting the "An attempt was made..." error, referencing the BatchParser DLL, on every ASP.NET MVC 3 page I opened, and that error was followed by dozens of page parsing errors.
If this happens to you, do a file search and see if the DLL is still in one of your project's \bin folders. Even if you do a rebuild, Visual Studio doesn't necessarily clear out everything in all your \bin folders. When I deleted the DLL from the bin and built again, the error went away.

I had this in an MVC5 app in Windows 10 against IIS Express. My solution was the following:
Tools =>
Options =>
Projects and Solutions =>
Web Projects =>
Use the 64 bit version of IIS Express for web sites and projects

change it to 32-bit (true) it works
if you get this Length cannot be less than zero. Parameter name: length issue in iis server configuation do the simple thing change the connection string in web.config file like your sql server name and server name and restart iis then try to load the page it works

If Publishing in Visual Studio 2012 when erroring try unchecking the "Procompile during publishing" option in the Publish wizard.

in windows form application I do this,
Right-click on Project->Properties->Build->Check Prefer 32-bit checkbox.
Thanks all

Delete the temp test directory located here
C:\Users(User)\AppData\Local\Temp\VisualStudioTestExplorerExtensions\
Set all projects to x64 in Visual Studio
Set the default processor architecture to x64(Test/TestSettings/Default Processor Architecture).
Make sure to clean build the solution file.Hope this helps!

Changing the Target Framework in project properties from .NET Framework 4.7.1 to 4.6.2 worked for me.