Hi. It could be just temporary fault - Umbraco RTE actually has no own spellchecker and relies on the Google spellchecking service (so that as the latter is unavailable the RTE spellchecker doesn't work as well).

It's returning this:

Error response:
Index and length must refer to a location within the string.
Parameter name: length

Server Error in '/' Application.

Index and length must refer to a location within the string.
Parameter name: length

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentOutOfRangeException: Index and length must refer to a location within the string.
Parameter name: length

Source Error:

Stack Trace:

 [ArgumentOutOfRangeException: Index and length must refer to a location within the string. Parameter name: length] System.String.InternalSubStringWithChecks(Int32 startIndex, Int32 length, Boolean fAlwaysCopy) +12681861 umbraco.presentation.umbraco_client.tinymce3.plugins.spellchecker.GoogleSpellChecker.CheckWords(String language, String[] words) +469 umbraco.presentation.umbraco_client.tinymce3.plugins.spellchecker.GoogleSpellChecker.ProcessRequest(HttpContext context) +247 System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +625 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +270 

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.272

Hi Jennifer,

IIRC there is a bug if you have single quotes (') in your content.  I think it's an issue with javascript not escaping them properly when sending your content to google.  Here is the bug report:  http://umbraco.codeplex.com/workitem/30215

Probably wouldn't be that hard to fix, maybe if I get some time I'll take a stab :)

-Tom

Had to fix this for a client, believe the problem is that the data sent to google for spellchecking is urlencoded, but when processing the result the data isn't so is a differing length, so just re-encoded the data before performing the substring, seems to work fine.

Beware this is just a quick fix and not extensively tested.

modify - /config/tinyMceConfig.config

<config key="spellchecker_rpc_url">GSpellChecker.ashx</config>

create - /umbraco/GSpellChecker.ashx

public class GSpellChecker : SpellChecker, IHttpHandler {
  // Methods
  public override SpellCheckerResult CheckWords(string language, string[] words) {
    XmlDocument document = new XmlDocument();
    string data = string.Join(" ", words);
    string xml = SendRequest(language, data);
    document.LoadXml(xml);
    data = HttpContext.Current.Server.UrlEncode(data);
    SpellCheckerResult result = new SpellCheckerResult();
    foreach (XmlNode node in document.SelectNodes("//c")) {
      XmlElement element = (XmlElement)node;
      result.result.Add(data.Substring(Convert.ToInt32(element.GetAttribute("o")), Convert.ToInt32(element.GetAttribute("l"))));
    }
    return result;
  }

  public override SpellCheckerResult GetSuggestions(string language, string word) {
    XmlDocument document = new XmlDocument();
    string xml = SendRequest(language, word);
    document.LoadXml(xml);
    SpellCheckerResult result = new SpellCheckerResult();
    foreach (XmlNode node in document.SelectNodes("//c")) {
      XmlElement element = (XmlElement)node;
      foreach (string str2 in element.InnerText.Split(new char[] { '\t' })) {
        if (!string.IsNullOrEmpty(str2)) {
          result.result.Add(str2);
        }
      }
    }
    return result;
  }

  public void ProcessRequest(HttpContext context) {
    SpellCheckerInput input = SpellCheckerInput.Parse(new StreamReader(context.Request.InputStream));
    SpellCheckerResult suggestions = null;
    string method = input.Method;
    if (method != null) {
      if (!(method == "checkWords")) {
        if (method == "getSuggestions") {
          suggestions = this.GetSuggestions(input.Language, input.Words[0]);
          goto Label_007C;
        }
      } else {
        suggestions = this.CheckWords(input.Language, input.Words.ToArray());
        goto Label_007C;
      }
    }
    suggestions = new SpellCheckerResult();
  Label_007C:
    suggestions.id = input.Id;
    string s = new JavaScriptSerializer().Serialize(suggestions);
    context.Response.Write(s);
  }

  private static string SendRequest(string lang, string data) {
    string str;
    string requestUriString = string.Format("https://www.google.com:443/tbproxy/spell?lang={0}&hl={0}", lang);
    string s = string.Format("<?xml version=\"1.0\" encoding=\"utf-8\" ?><spellrequest textalreadyclipped=\"0\" ignoredups=\"0\" ignoredigits=\"1\" ignoreallcaps=\"1\"><text>{0}</text></spellrequest>", HttpContext.Current.Server.UrlEncode(data));
    StreamReader reader = null;
    HttpWebResponse response = null;
    Stream requestStream = null;
    try {
      HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUriString);
      request.KeepAlive = false;
      request.Method = "POST";
      request.ContentType = "application/PTI26";
      request.ContentLength = s.Length;
      WebHeaderCollection headers = request.Headers;
      headers.Add("MIME-Version: 1.0");
      headers.Add("Request-number: 1");
      headers.Add("Document-type: Request");
      headers.Add("Interface-Version: Test 1.4");
      requestStream = request.GetRequestStream();
      byte[] bytes = new ASCIIEncoding().GetBytes(s);
      requestStream.Write(bytes, 0, bytes.Length);
      response = (HttpWebResponse)request.GetResponse();
      reader = new StreamReader(response.GetResponseStream());
      str = reader.ReadToEnd();
    } finally {
      if (requestStream != null) {
        requestStream.Close();
      }
      if (reader != null) {
        reader.Close();
      }
      if (response != null) {
        response.Close();
      }
    }
    return str;
  }

  // Properties
  public bool IsReusable {
    get {
      return false;
    }
  }
}

Thanks Mark, just that to help other dummies (like me): it requires the following "using"s

using System;
using System.Web;
using umbraco.presentation.umbraco_client.tinymce3.plugins.spellchecker;
using System.Xml;
using System.IO;
using System.Web.Script.Serialization;
using System.Net;
using System.Text;

The Google spellchecker service this relies on (https://www.google.com/tbproxy/spell) may have been turned off for good.

An alternative is the HunSpellChecker plugin

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