Simple C# function to generate random passwords:
Random randomizer = new Random();
public string CreateTemporaryPassword(int length)
{
string letters = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
var chars = new char[length];
for (int i = 0; i < length; i++)
chars[i] = letters[randomizer.Next(0, letters.Length)];
return new string(chars);
}
Joel Holder's Code Compendium 