I inherited some code two weeks ago that is using the jquery.ajax method to connect to a .NET web service. Here is the piece of code give me the trouble...

if (MSCTour.AppSettings.OFFLINE !== 'TRUE') {
        $.ajax({
            url: url,
            data: json,                
            type: "POST",                
            contentType: "application/json",
            timeout: 10000,
            dataType: "json", // not "json" we'll parse
            success: function(res){                  
                if (!callback) {
                    return;
                }

                /*
                 // *** Use json library so we can fix up MS AJAX dates
                 */
                var result = "";

                if (res !== "") {  
                  try {
                    result = $.evalJSON(res);
                  }
                  catch (e) {
                    result = {};
                    bare = true;
                  }
                }                    
                /*
                 // *** Bare message IS result
                 */                   
                if (bare) {                      
                    callback(result);
                    return;
                }

                /*
                 // *** Wrapped message contains top level object node
                 // *** strip it off
                 */
                for (var property in result) {
                    callback(result[property]);
                    break;
                }
            },
            error: function(xhr,status,error){
                if (status === 'parsererror') {}
                else {return error;}
            },
            complete: function(res, status){                  

                if (callback) {
                    if ((status != 'success' && status != 'error') || status === 'parsererror' || (status === 'timeout' && res !== '')) {
                      try {
                        result = $.secureEvalJSON(res);
                      }
                      catch (e) {
                        result = {};
                        bare = true;
                      }
                      callback(res);
                    }
                }
                return;
            }
        });
    }

The url variable at this point equals /testsite/service.svc/GetItems

Now here is where my problem lies...

When running this site out of debug mode through visual studio I am not having any problem connecting to the database through the web service and seeing all my data, for both viewing and updating. When I go through the normal web server for the same site, on the same page, no data is showing up. When I put a break on the error portion of the code above in firebug this is information I am getting in the image linked below.

link text

I am getting what appears to be a 404 error, but when I look on the server all of the files are in the right place... coupled with the fact that it works when in debug mode, I think I am slowly going crazy staring at these same lines of code trying to find the needle in the haystack. Any help or just a direction to look in would be greatly appreciated.