Hi! I'm developing a client-server application in c# using WSE web-service. One of the things that the user can do is send jpg images to the server for backup via the web-service. Recently strange errors have occurred. This does not happen for all users, just a few. On the client side the exception is a

System.Net.WebException Exception message: The operation has timed out

and on the server the following warning is found in the event viewer:

Exception information:      
Exception type: HttpException
Exception message: Server cannot clear headers after HTTP headers have been sent.
Request information
Request URL: MyUrl/Service.asmx
Request path: /MyWebService/Service.asmx
User host address: -------
User:
Is authenticated: False
Authentication Type:
Thread account name: NT AUTHORITY\NETWORK SERVICE
Thread information:
Thread ID: 7
Thread account name: NT AUTHORITY\NETWORK SERVICE
Is impersonating: False
Stack trace: at System.Web.HttpResponse.ClearHeaders()
at System.Web.Services.Protocols.SoapServerProtocol.WriteException(Exception e, Stream outputStream)
at System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing)
at System.Web.Services.Protocols.WebServiceHandlerFactory.CoreGetHandler(Type type, HttpContext context, HttpRequest request, HttpResponse response)

Does anyone have an idea where this error can come from? I have already tried to raise the "maxRequestLength" in web.config to 16Mb but this doesn't fix it.

Regards /Daniel