code wont continue after a certain method is called

Question

I have a few lines

 Encryption enc = new Encryption();
 enc.SendAsymetricencrypt(client.GetStream(), rsa);

it goes in to SendAsymetricencrypt just fine, problem is that it never comes out

 public void SendAsymetricencrypt(NetworkStream clientsStream, RSA rsa)
    {

        //at the start of client he creates an asymetric key and 
        //sending it to the server so the server could send back 
        //safely the symetric key
        RSAParameters publickeyInfo = rsa.ExportParameters(false);

        //<summry>
        //sends the Modulus
        //</summry>
        //just the length of mod
        string ModLen = publickeyInfo.Modulus.Length.ToString();
        //make md to array
        byte[] addMD = Encoding.ASCII.GetBytes("@@@MD");
        //prepare a new array with the requierd length
        byte[] byteDataMod = new byte[int.Parse(ModLen) + addMD.Length];
        //add addOn to array
        addMD.CopyTo(byteDataMod, 0);
        // add the mod to array
        publickeyInfo.Modulus.CopyTo(byteDataMod, addMD.Length);

        //send
        clientsStream.Write(byteDataMod, 0, byteDataMod.Length);
        clientsStream.Flush();
        //<summry>
        //sends the exponent
        //</summry>
        //just the length of ex
        string ExLen = publickeyInfo.Exponent.Length.ToString();
        //make ex to array
        byte[] addEX = Encoding.ASCII.GetBytes("@@@EX");
        //prepare a new array with the requierd length
        byte[] byteDataEx = new byte[int.Parse(ExLen) + addEX.Length];
        //add addOn to array
        addEX.CopyTo(byteDataEx, 0);
        // add the mod to array
        publickeyInfo.Exponent.CopyTo(byteDataEx, addEX.Length);

        //send
        clientsStream.Write(byteDataEx, 0, byteDataEx.Length);
        clientsStream.Flush();


    }

debuging shows the program gets to the last line executes it and then just doesn't come back out to complete the rest of the code.

past the call I have

    enc.SendAsymetricencrypt(client.GetStream(), rsa);
        try
        {
            client.GetStream().BeginRead(data,
                                               0,
                                               System.Convert.ToInt32(client.ReceiveBufferSize),
                                               ReceiveMessage,
                                               null);
        }
        catch(Exception ex)
        {
            MessageBox.Show(Convert.ToString(ex));
        }

I have a breakpoint at the try but it never even gets there.

what an u doing wrong?

I already checked and the bytes do get to the server just fine