AppHarbor Precompilation Error

When deployed to AppHarbor, AppHarbor provided me with the following compilation output:

Microsoft (R) ASP.NET Compilation Tool version 4.0.30319.17929
Utility to precompile an ASP.NET application
Copyright (C) Microsoft Corporation. All rights reserved.

D:\temp\cprt3dr0.2g3\output\_PublishedWebsites\WebMatrixWebsite\gnsystem\gnsystem\web.config(24): error ASPCONFIG: It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level.  This error can be caused by a virtual directory not being configured as an application in IIS.

[ConfigurationErrorsException]: It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level.  This error can be caused by a virtual directory not being configured as an application in IIS. (D:\temp\cprt3dr0.2g3\output\_PublishedWebsites\WebMatrixWebsite\gnsystem\gnsystem\web.config line 24)
   at System.Configuration.ConfigurationSchemaErrors.ThrowIfErrors(Boolean ignoreLocal)
   at System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject)
   at System.Configuration.BaseConfigurationRecord.GetSection(String configKey)
   at System.Web.Configuration.RuntimeConfig.GetSectionObject(String sectionName)
   at System.Web.Configuration.RuntimeConfig.GetSection(String sectionName, Type type, ResultsIndex index)
   at System.Web.Configuration.RuntimeConfig.get_Compilation()
   at MTConfigUtil.GetCompilationConfig(String vpath)
   at System.Web.Compilation.WebDirectoryBatchCompiler..ctor(VirtualDirectory vdir)
   at System.Web.Compilation.BuildManager.BatchCompileWebDirectoryInternal(VirtualDirectory vdir, Boolean ignoreErrors)
   at System.Web.Compilation.BuildManager.BatchCompileWebDirectory(VirtualDirectory vdir, VirtualPath virtualDir, Boolean ignoreErrors)
   at System.Web.Compilation.BuildManager.PrecompileWebDirectoriesRecursive(VirtualDirectory vdir, Boolean topLevel)
   at System.Web.Compilation.BuildManager.PrecompileWebDirectoriesRecursive(VirtualDirectory vdir, Boolean topLevel)
   at System.Web.Compilation.BuildManager.PrecompileWebDirectoriesRecursive(VirtualDirectory vdir, Boolean topLevel)
   at System.Web.Compilation.BuildManager.PrecompileWebDirectoriesRecursive(VirtualDirectory vdir, Boolean topLevel)
   at System.Web.Compilation.BuildManager.PrecompileAppInternal(VirtualPath startingVirtualDir, IEnumerable`1 excludedVirtualPaths)
   at System.Web.Compilation.BuildManager.PrecompileApp(VirtualPath startingVirtualDir, IEnumerable`1 excludedVirtualPaths)
   at System.Web.Compilation.BuildManager.PrecompileApp(ClientBuildManagerCallback callback, IEnumerable`1 excludedVirtualPaths)
   at System.Web.Compilation.BuildManagerHost.PrecompileApp(ClientBuildManagerCallback callback, List`1 excludedVirtualPaths)
   at System.Web.Compilation.BuildManagerHost.PrecompileApp(ClientBuildManagerCallback callback, List`1 excludedVirtualPaths)
   at System.Web.Compilation.ClientBuildManager.PrecompileApplication(ClientBuildManagerCallback callback, Boolean forceCleanBuild)
   at System.Web.Compilation.ClientBuildManager.PrecompileApplication(ClientBuildManagerCallback callback)
   at System.Web.Compilation.Precompiler.Main(String[] args)




Website precompilation failed with exit code 1. Precompilation can optionally be disabled in application settings

After searching the Internet, I found several solutions indicating that I should clear my solution and configure my application folder as a virtual folder in IIS.

I did the first one (and it didn't work), but I have no idea how to make the second from AppHarbor, any suggestions?

Edit1 : Web.Config