Problème NRJ Chat . Aidez-moi svp

Bonjour,
J'ai un problème avec le chat NRJ depuis déjà de nombreux mois. Tout d'abord, j'arrive à me connecter. Pas de soucis. Mais ensuite, d'une part, je ne reçois aucun message ( j'ai même essayer de m'envoyer un message à moi-même, mais je ne l'ai pas reçu) et lorsque je clique sur Rechercher, voici le code d'erreur qui apparaît :

Server Error in '/' Application.
No stylesheet was loaded.
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.InvalidOperationException: No stylesheet was loaded.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[InvalidOperationException: No stylesheet was loaded.]
System.Xml.Xsl.XslTransform.CheckCommand() +3949549
System.Xml.Xsl.XslTransform.Transform(XPathNavigator input, XsltArgumentList args, TextWriter output, XmlResolver resolver) +16
System.Xml.Xsl.XslTransform.Transform(IXPathNavigable input, XsltArgumentList args, TextWriter output, XmlResolver resolver) +43
System.Web.UI.WebControls.Xml.Render(HtmlTextWriter output) +8662100
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
System.Web.UI.Page.Render(HtmlTextWriter writer) +29
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1266

Version Information: Microsoft .NET Framework Version:2.0.50727.4016; ASP.NET Version:2.0.50727.4016

Pouvez-vous m'aider à résoudre ce problème s'il vous plait ?
Merci d'avance =)