IndexOutOfRangeException - Windows Phone (C#)

I am getting know with Windows Phone, and C# as well. I found out that there is an
IndexOutOfRangeException in my Coloring() function:

public void Coloring()
     {
         szinek_base.Add(Color.FromArgb(255, 0, 171, 169));
         szinek_base.Add(Color.FromArgb(255, 140, 191, 38));
         szinek_base.Add(Color.FromArgb(255, 160, 80, 0));
         szinek_base.Add(Color.FromArgb(255, 230, 113, 184));
         szinek_base.Add(Color.FromArgb(255, 240, 150, 9));
         szinek_base.Add(Color.FromArgb(255, 27, 161, 226));
         szinek_base.Add(Color.FromArgb(255, 229, 20, 0));
         szinek_base.Add(Color.FromArgb(255, 51, 153, 51));
         int remove;
         Color szin = new Color();
         Random generator = new Random();
         List<int> lapok = new List<int>();
         for (int l = 0; l < 16; l++)
         {
             lapok.Add(l);
         }
 
         for (int i = 0; i < 8; i++)
         {   
                 szin = szinek_base[generator.Next(0, szinek_base.Count)]; 
 
                 remove = lapok[generator.Next(0, lapok.Count)]; 
                 szinek[remove] = szin;
                 lapok.Remove(remove);
                 szinek_base.Remove(szin);
 
                 remove = lapok[generator.Next(0, lapok.Count)];
                 szinek[remove] = szin;
                 lapok.Remove(remove);
                 szinek_base.Remove(szin);
         }
     }
 

Using try-catch i also found out that the second for() cycle contains the bug.
However if i split into half the block and using try-catch, it wont find error nor in the first part
neither the second. This code works fine under windows 7 as part of a memory game by the way, i am out of ideas.
Thanks for the help, and sorry for grammatic and other mistakes, i am not aware of StackOverflow protocol, yet.

Edit: Forgot to mention, the main namespace contains them:

public List<Color> szinek_base = new List<Color>();
 Color[] szinek = new Color[8];
 

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