diff --git a/MappingGenerator/MappingGenerator/MappingGenerator/MappingGenerator.cs b/MappingGenerator/MappingGenerator/MappingGenerator/MappingGenerator.cs
index a0cd78b..6669f35 100644
--- a/MappingGenerator/MappingGenerator/MappingGenerator/MappingGenerator.cs
+++ b/MappingGenerator/MappingGenerator/MappingGenerator/MappingGenerator.cs
@@ -160,11 +160,19 @@ private SyntaxNode MapCollections(SyntaxNode sourceAccess, ITypeSymbol sourceLis
             return WrapInReadonlyCollectionIfNecessary(isReadolyCollection, toList, generator);
         }
 
-        private static ITypeSymbol GetElementType(ITypeSymbol collectionType)
+        private ITypeSymbol GetElementType(ITypeSymbol collectionType)
         {
             switch (collectionType)
             {
                 case INamedTypeSymbol namedType:
+                    if (namedType.IsGenericType == false)
+                    {
+                        if (ObjectHelper.IsSystemObject(namedType.BaseType))
+                        {
+                            return namedType.BaseType;
+                        }
+                        return GetElementType(namedType.BaseType);
+                    }
                     return namedType.TypeArguments[0];
                 case IArrayTypeSymbol arrayType:
                     return arrayType.ElementType;
@@ -193,8 +201,8 @@ private static SyntaxNode WrapInReadonlyCollectionIfNecessary(bool isReadonly, S
 
         private static bool IsMappingBetweenCollections(ITypeSymbol targetClassSymbol, ITypeSymbol sourceClassSymbol)
         {
-            return (HasInterface(targetClassSymbol, "System.Collections.Generic.ICollection<T>") || targetClassSymbol.Kind == SymbolKind.ArrayType)
-                   && (HasInterface(sourceClassSymbol, "System.Collections.Generic.IEnumerable<T>") || sourceClassSymbol.Kind == SymbolKind.ArrayType);
+            return (HasInterface(targetClassSymbol, "System.Collections.ICollection") || targetClassSymbol.Kind == SymbolKind.ArrayType)
+                   && (HasInterface(sourceClassSymbol, "System.Collections.IEnumerable") || sourceClassSymbol.Kind == SymbolKind.ArrayType);
         }
 
         private ArgumentListSyntax FindMappingConstructorParameters(ITypeSymbol targetType, ITypeSymbol sourceType, ObjectMembersMappingSourceFinder mappingSourceFinder, ExpressionSyntax globalSourceAccessor)
diff --git a/MappingGenerator/MappingGenerator/MappingGenerator/ObjectHelper.cs b/MappingGenerator/MappingGenerator/MappingGenerator/ObjectHelper.cs
index 26d7ede..94255bb 100644
--- a/MappingGenerator/MappingGenerator/MappingGenerator/ObjectHelper.cs
+++ b/MappingGenerator/MappingGenerator/MappingGenerator/ObjectHelper.cs
@@ -70,7 +70,7 @@ private  static IEnumerable<ITypeSymbol> GetBaseTypesAndThis(ITypeSymbol type)
             }
         }
 
-        private static bool IsSystemObject(ITypeSymbol current)
+        public static bool IsSystemObject(ITypeSymbol current)
         {
             return current.Name == "Object" && current.ContainingNamespace.Name =="System";
         }