Virtual method that takes a vector of a specific type in parameter

Question

I'm trying make a virtual method that takes a vector of a specific type in parameter.

This is the parent class:

template <typename T>
class Syncable
{
    virtual void update(vector<typename T::PropertyType>& properties) = 0
};

This is the child class:

class MyUser : public Syncable <MyUser>
{
public:
    enum class Property
    {
        Id,
        DisplayName
    };
    using PropertyType = Property;

    virtual void update(vector<PropertyType>& properties) override
    {
        cout << "Update";
    }
};

However, I get the following error:

error C2039: 'PropertyType': is not a member of 'MyUser

I think it might say so because in the Syncable class, MyUser is not defined yet. How can I workaround this problem?

I use Visual Studio 2015.