Generating Random Password

public string passGenerate(int len)
{
string _passGenerate = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890!@#$&*?";
string _myNewPassword = "";
Random rnd = new Random();
for (int i = 0; i < len; i++)
{
_myNewPassword += _passGenerate.ToCharArray()[rnd.Next(0,69)].ToString();
}
return _myNewPassword;
}