Overview

A user is trying to add a custom module recently installed to one of their pages but encounters the following error.

[ERROR] DotNetNuke.Web.InternalServices.ControlBarController - System.NullReferenceException: Object reference not set to an instance of an object.
at DotNetNuke.Entities.Modules.ModuleController.AddModule(ModuleInfo module)
at DotNetNuke.Web.InternalServices.ControlBarController.DoAddNewModule(String title, Int32 desktopModuleId, String paneName, Int32 position, Int32 permissionType, String align)
at DotNetNuke.Web.InternalServices.ControlBarController.AddModule(AddModuleDTO dto)

Solution

If the module was properly installed, one possible cause for this error is that the cached information for this module is invalid and one would need to Clear the Application Cache. In case the issue persists after clearing the case, Recycle the Application Pool as well.