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I am trying to use AutoMapper for the first time and have some problems with it. My code is below and I get error below. Maybe someone could show how to map the list of models? 

cannot convert from 'System.Linq.IQueryable<AnonymousType#1>' to 'Entity.Product' C:\Users\Administrator\Projects\PC\trunk\PC\Controllers\AdminController.cs 37 100 PC 
public class ProductViewModel { public int Id { get; set; } public string Name { get; set; } public int UsersCount { get; set; } } var products = _repository.GetProducts(true).Select(p=> new { p.Id, p.Name, UsersCount = 0 }); Mapper.CreateMap<Product, ProductViewModel>(); ViewData["Products"] = Mapper.Map<IEnumerable<Product>, IEnumerable<ProductViewModel>>(products); //Error appears on products object //Product domain model(linq2sql generated model) public partial class Product : INotifyPropertyChanging, INotifyPropertyChanged { private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty); private int _Id; private bool _Active; private System.Nullable<int> _Sort; private System.Nullable<int> _Category; private string _Name; private int _ProductTypeId; private decimal _Price; private System.Nullable<int> _Months; private System.Nullable<int> _Credits; private string _Features; private string _BlockReason; private string _BuyUrl1; private string _BuyUrl2; private bool _UsersManager; }
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In your LINQ query you select an anonymous object. Make sure you select a Product which is your source type (or more specifically IEnumerable<Product>):

IEnumerable<Product> products = _repository.GetProducts(true); IEnumerable<ProductViewModel> productsViewModel = Mapper.Map<IEnumerable<Product>, IEnumerable<ProductViewModel>>(products); return View(productsViewModel);

Also do not call Mapper.CreateMap<TSource, TDest> inside your controller action. This must be called only once in the lifetime of the AppDomain, ideally in your Application_Start.

Also notice that I have gotten rid of ViewData which is a great thing. You don't need ViewData. You are working with view models. That's what they are supposed to do. Contain information that will be needed by your view in a strongly typed manner.

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I need to create UsersCount field which is calculated field. In example above I just assigned UsersCount = 0 but in real app I will need to calculate Users and assign them to UsersCount property. Maybe my design is wrong? How to change it?
I don't know what's your design so that I can tell you if it is wrong or not. How is this field calculated? On what information from your domain model does it depend? How does your Product domain model look like?
My database look like Products - > Users. When I query Products using linq to sql in GetProducts method I get list of products. After that I need to count how much users assigned to specified product. So I add new field UsersCount and I will add linq to sql query to this field to perform user counting.
I repeat my question: how does your Product model look like? That's all I need to know. That's all the information you pass as argument to AutoMapper in order to convert it to a view model. AutoMapper doesn't know anything about databases and tables. It works with .NET classes as input and spits .NET classes as output.
I am seeing only private fields in this Product class. Where's the other part of this partial class? Also how are the users related to it? How do you know the number of users associated to a Product given a Product instance? If you don't know this you cannot configure AutoMapper to map this property. AutoMapper works only with one source type to one destination type.

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