while trying to insall any of my custom modules to a local (xp) 4.5.1 site i get this message

ExceptionSystem.NullReferenceException: Object reference not set to an instance of an object. at DotNetNuke.Common.Utilities.Config.AddCodeSubDirectory(String name) at DotNetNuke.Modules.Admin.ResourceInstaller.PaDnnInstallerBase.CreateModuleFile(PaFile File, PaFolder Folder) at DotNetNuke.Modules.Admin.ResourceInstaller.PaDnnInstallerBase.CreateFiles(PaFolder Folder) at DotNetNuke.Modules.Admin.ResourceInstaller.PaDnnInstallerBase.Install(PaFolderCollection folders) at DotNetNuke.Modules.Admin.ResourceInstaller.PaInstaller.Install()

Full permissions are granted to the ASP.Net account. I have no problem deploying these to other sites (4.4.1) on other servers (w2k3).

VB, all the way.

I checked the dnn file and I found that all the files that should go in the app_code folder had entries like this:

<file>
<path>[app_code]</path>
<name>DataProvider.vb</name>
</file>

So I removed the brackest around [app_code] and the install went fine, no errors. But it didn't create the directory under the app_code folder, but it did create the app_code folder under the module folder (desktop modules\modulename\app_code).

Do I have to specify where the app_code folder is in the DNN file? The module was packaged using the module definitions and I had checked the create manifest file option.