Sharepoint server 2007, Excel services and Windows server 2003

Question

Hello,

we are developping an application using Sharepoint server 2007 and Excel Services. Works great under windows 2008 but won't in windows 2003 server.

We always get a System.Web.Services.Protocols.SoapException when trying to create an Excel services session.

Any ideas about this ?

[System.Web.Services.Protocols.SoapDocumentMethodAttribute("http://schemas.microsoft.com/office/excel/server/webservices/OpenWorkbook", RequestNamespace="http://schemas.microsoft.com/office/excel/server/webservices", ResponseNamespace="http://schemas.microsoft.com/office/excel/server/webservices", Use=System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] 

public string OpenWorkbook(string workbookPath, string uiCultureName, string dataCultureName, out Status[] status) {

            object[] results = this.Invoke("OpenWorkbook", new object[] {

                        workbookPath,

                        uiCultureName,