Hello, We built our application(web application) on MS SQL Server(windows 7 64bit) using Dataobjects.net 4.6.4 and it works fine, now we need to convert it to Oracle database, so i downloaded Oracle database 11g release 2(client and server components), referencing Xtensive.Orm.Oracle and Oracle.DataAccess DLLs. then changed my connection string to refer to the new oracle database, but when starting the application, I got the following error:

Could not load file or assembly 'Oracle.Web' or one of its dependencies. An attempt was made to load a program with an incorrect format.

with the following stack trace:

[BadImageFormatException: Could not load file or assembly 'Oracle.Web' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Reflection.RuntimeAssembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, RuntimeAssembly locationHint, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +0
   System.Reflection.RuntimeAssembly.InternalLoadAssemblyName(AssemblyName assemblyRef, Evidence assemblySecurity, RuntimeAssembly reqAssembly, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean throwOnFileNotFound, Boolean forIntrospection, Boolean suppressSecurityChecks) +210
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, IntPtr pPrivHostBinder, Boolean forIntrospection) +242
   System.Reflection.RuntimeAssembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection) +17
   System.Reflection.Assembly.Load(String assemblyString) +35
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +122

[ConfigurationErrorsException: Could not load file or assembly 'Oracle.Web' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Web.Configuration.CompilationSection.LoadAssemblyHelper(String assemblyName, Boolean starDirective) +12846746
   System.Web.Configuration.CompilationSection.LoadAllAssembliesFromAppDomainBinDirectory() +503
   System.Web.Configuration.AssemblyInfo.get_AssemblyInternal() +142
   System.Web.Compilation.BuildManager.GetReferencedAssemblies(CompilationSection compConfig) +334
   System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded) +148
   System.Web.Compilation.BuildManager.ExecutePreAppStart() +172
   System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException) +1151

[HttpException (0x80004005): Could not load file or assembly 'Oracle.Web' or one of its dependencies. An attempt was made to load a program with an incorrect format.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +12968244
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +159
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +12807949