I'm trying to use Visual Studio to develop and debug a web application that uses the SharePoint 2007 API. I have been doing this fine on a 32-bit server up until now. Today I've moved over to a 64-bit development server and when I try to run the project out of VS, I get:
Could not load file or assembly 'Microsoft.SharePoint.Search, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c' or one of its dependencies. An attempt was made to load a program with an incorrect format.
I have referenced Microsoft.SharePoint.dll and Microsoft.SharePoint.intl.dll from the GAC on this machine. That automatically copies in Microsoft.SharePoint.Search.dll from somewhere when I run it (even though copy local is false on the references). My project Platform Target is "Any CPU". I get the same error with x86. If I change to x64, I instead get Could not load file or assembly 'MyProjects.dll'...incorrect format.. I've also tried deleting Microsoft.SharePoint.Search.dll from the bin after it starts up but then I get a SharePoint error saying that the site at my URL can't be found, which I believe is also a bitness issue. I'm not quite sure what the issue is but want to be able to run this application out of Visual Studio. How can I get it working?
Both Microsoft.SharePoint.dll and Microsoft.SharePoint.intl.dll in the server's GAC are built for Any CPU. When I build my web app in Visual Studio, it automatically copies Microsoft.SharePoint.Search.dll into my bin, presumably because it's referenced by Microsoft.SharePoint.dll. SharePoint.Search.dll is not in the GAC. It is copied from the 64-bit 12\ISAPI directory and is built with an "Amd64" target architecture (despite my server having an Intel Xeon CPU). So I believe the problem is VS runs the web app in a 32-bit process which causes the error when it tries to load the 64-bit SharePoint.Search.dll.
My first idea was to explicitly reference the 32-bit SharePoint.Search.dll in my project. That makes the error go away but it is replaced with an error saying the website at [my SharePoint site URL] cannot be found. I believe this is because now I'm trying to access the SharePoint site, which runs in a 64-bit app pool, from a 32-bit process. So what I really need is for Visual Studio to run my web app using a 64-bit hosting process. This looks like an option available for VS 2012, but not 2010. The alternatives I've found for VS 2010 are:
On the project properties Web tab, configure it to run using the Local IIS instance. This will add a virtual directory to the default site, which is running in 64-bit mode by default. This isn't a good solution for me because I want to allow multiple developers to work on the same project on the same server simultaneously. Using the same site would cause conflicts. If there were a way to configure the site name conditionally on the user, this would be ok. I opted to try #2 first.
Replace the VS Development Server with an x64 build of the CassiniDev project. This project has the capability of plugging in to VS in place of the default WebDev.WebServer.EXE. So you just need to download the source code, and build with an x64 target platform. Then you can replace the VS default development server exe, as is documented w/ the CassiniDev project, and it will run an x64 development web server which solves my problem!