Accessing a value in a static method

Hi,

I have this code:

        public static void DownloadLastPostStringInBackground(string address)
        {
            WebClient client = new WebClient();
            Uri uri = new Uri(address);

            // Specify that the DownloadStringCallback method gets called
            // when the download completes.
            client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(DownloadLastPostStringCallback);
            client.DownloadStringAsync(uri);
        }

        private static void DownloadLastPostStringCallback(Object sender, DownloadStringCompletedEventArgs e)
        {
            // If the request was not canceled and did not throw
            // an exception, display the resource.
            if (!e.Cancelled && e.Error == null)
            {
                string textString = (string)e.Result;

                Check(Convert.ToInt32(textString));
            }
        }

Now Check() method called from DownloadLastPostStringCallback is not a static method (I can't make it static because I'm changing the properties of some control from it) and therefore I'm getting an error message saying:

Error      1      An object reference is required for the nonstatic field, method, or property '....FormStartup.Check(int)'      ...      225      17      ...

Your help would be appreciated.