"Unable to load data" error after Windows update

Question

Hi all,
I've been maintaining a LightSwitch desktop app for a couple of years now.  The app runs on a server and several client machines access it.  Sometime in the last few months, any client that has Windows Update enabled has failed to load data.  Instead
it shows red crosses where the data should be and the tooltip, "Unable to load data. Please check your connection and try loading again."
Other clients that don't have updates enabled are fine.  Has anyone else run into this issue?  Does anyone know how to resolve it?
Thanks,
Liam

Answer 1

Hi Angie,
Thanks for your reply.  I've enabled diagnostics as described.  Here's what I find.
When I load my LightSwitch screen, I get the following entry highlighted red in Fiddler:
GET http://127.0.0.1:6853/callback.json?_=1377245349573
502 Fiddler - Connection Failed (text/html)
GET http://127.0.0.1:6853/callback.json?_=1377245349573 HTTP/1.1
Host: 127.0.0.1:6853
Proxy-Connection: keep-alive
Accept: application/json, text/javascript, */*; q=0.01
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.57 Safari/537.36
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-GB,en;q=0.8
HTTP/1.1 502 Fiddler - Connection Failed
Date: Fri, 23 Aug 2013 08:09:10 GMT
Content-Type: text/html; charset=UTF-8
Connection: close
Timestamp: 09:09:10.584
[Fiddler] The socket connection to 127.0.0.1 failed. <br />ErrorCode: 10061. <br />No connection could be made because the target machine actively refused it 127.0.0.1:6853
After that, I see a long list of each of the queries LightSwitch is calling for all the elements on the screen.  Each one contains the following error:
HTTP/1.1 200 OK
Cache-Control: no-cache
Pragma: no-cache
Content-Length: 747
Content-Type: application/msbin1
Expires: -1
Server: Microsoft-IIS/7.5
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
Date: Fri, 23 Aug 2013 08:10:38 GMT
@Fault5http://schemas.microsoft.com/ws/2005/05/envelope/none@Code@Value�Sender@Reason@Textxmllang�en-GB��<?xml version="1.0" encoding="utf-16"?><ExceptionInfo><Message>User does not have access to the invoked operation. Your session may have timed out. Please restart the application. Operation name: 'HSEComments_All'.</Message></ExceptionInfo>@Detail@DomainServiceFaultDomainServices i)http://www.w3.org/2001/XMLSchema-instance@ ErrorCode�@ErrorMessage��<?xml version="1.0" encoding="utf-16"?><ExceptionInfo><Message>User does not have access to the invoked operation. Your session may have timed out. Please restart the application. Operation name: 'HSEComments_All'.</Message></ExceptionInfo>@IsDomainException�
Can you help in interpreting these?
Thanks,
Liam