InfoPath Dev

Hi, wonder if someone can help me with this error:

I am trying to submit a form and then after the submit to update a column using the code below, however I am getting the following error:

"The OnSubmitRequest event handler did not work" and in the details was this error "Could not load file or assembly 'Microsoft.SharePoint, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c' or one of its dependencies. The system cannot find the file specified." but when I run it on the SP server it runs fine ... only when I run it from outside the server I get the above mentioned errors.

Any ideas? suggestions?

Thanks

Steve

            SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                SPWeb site = new SPSite("http://serverurl/").OpenWeb();
                SPFolder folder = site.GetFolder("Multi Form Approval");
                SPFileCollection files = folder.Files;

                try
                {
                    foreach (SPFile file in files)
                    {
                        if (file.Item.Name == fileName.Trim() + ".xml")
                        {
                            file.Item["Manager Name"] = managerName;
                            site.AllowUnsafeUpdates = true;
                            file.Item.Update();
                            site.AllowUnsafeUpdates = false;
                        }
                    }
                }
                catch(Exception ex)
                {
                    Console.WriteLine(ex.Message);               
                }
            });
            // If the submit operation is successful, set
            e.CancelableArgs.Cancel = false;
            // Write your code here.
            }