Yesterday I worked on a project where I upgraded to Entity Framework 4 with the Repository pattern. In one post, I have read that it is necessary to turn off the custom tool generator classes and then write classes (same like entites) by hand. That I can do it, I used the POCO Entity Generator and then deleted the new generated files .tt and all subordinate .cs classes. Then I wrote the "entity classes" by myself.

I added the repository pattern and implemented it in the business layer and then implemented a WCF layer, which should call the methods from the business layer. By calling an Insert (Add) method from the presentation layer and everything is OK. But if I call any method that should return some class, then I get an error like (the connection was interrupted by the server).

I suppose there is a problem with the serialization or am I wrong? How can by this problem solved?

I'm using Visual Studio S2010, Entity Framework 4, C#.

UPDATE:

I have uploaded the project and hope somebody can help me! link text

UPDATE 2:

My questions:

1. Why is POCO good (pros/cons)?
2. When should POCO be used?
3. Is POCO + the repository pattern a good choice?
4. Should POCO classes by written by myself or could I use auto generated POCO classes?