Hi, I am facing a problem. The description is below, Log Name: Application Source: Application Error Date: 18-10-2011 12:40:57 Event ID: 1000 Task Category: (100) Level: Error Keywords: Classic User: N/A Computer: TESTMACHINE Description: Faulting application name: WCFService.exe, version: 1.0.0.0, time stamp: 0x4e991373 Faulting module name: ntdll.dll, version: 6.1.7601.17514, time stamp: 0x4ce7b96e Exception code: 0xc0000005 Fault offset: 0x00056018 Faulting process id: 0x%9 Faulting application start time: 0x%10 Faulting application path: %11 Faulting module path: %12 Report Id: %13 Event Xml: <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event"> <System> <Provider Name="Application Error" /> <EventID Qualifiers="0">1000</EventID> <Level>2</Level> <Task>100</Task> <Keywords>0x80000000000000</Keywords> <TimeCreated SystemTime="2011-10-18T07:10:57.000000000Z" /> <EventRecordID>22672</EventRecordID> <Channel>Application</Channel> <Computer>TESTMACHINE</Computer> <Security /> </System> <EventData> <Data>WCFService.exe</Data> <Data>1.0.0.0</Data> <Data>4e991373</Data> <Data>ntdll.dll</Data> <Data>6.1.7601.17514</Data> <Data>4ce7b96e</Data> <Data>c0000005</Data> <Data>00056018</Data> </EventData> </Event> I have one WCF service deployed. That service communicate with network using one DLL developed in VC++. I tried reproduce the issue by loading symbols and enabling unmanaged code debugging in Visual Studio 2008. I managed to find one function in the VC++ DLL function generating error is using two Winsock2 functions 1. select and then 2. send. This error is random in nature. The machine is Windows 7 32-bit. This seems working fine on Windows XP machine. How can I move forward from here?Regards, Jignesh

Check out this KB - it might be relevant: http://support.microsoft.com/kb/2536401

Thanks JamesBannan for your time. I already looked into the link you provided but its totally different issue. For one of our customer who was facing this problem, we applied the MS Patch as described in the post and it fixed the problem. The error description of that problem was "Source: SMSvcHost 3.0.0.0, Description: An error occurred while dispatching a duplicated socket: this handle is now leaked in the process." The issue described above has something to do with Windows 7 (I suspect) because I have not observed it on Windows XP. It is random in nature. Anything else which get me closure to the resolution of that issue? I appreciate your inputs.Regards, Jignesh

Hi, I notice the DLL file associated with WCF service is developed by yourself. Please understand Windows 7 works different from Windows XP. It might have compatible issue in Windows 7 although it works in Windows XP. Please contact MSDN forum to get more assistance for your development issue. http://social.msdn.microsoft.com/Forums/en-US/vcgeneral/threads Best Regards, Niki Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Thanks Niki for your inputs. I agree with you and have the same confusion. It looks the compatibility issue with Windows 7. I tried to post it on MS-Connect but it got closed as Not Reproducible. I had googled for that compatibility and found that link. But I didn't get chance to test it yet. I want to reproduce this issue frequently 3-4 times and then check again after applying the compatibility changes. This is only way I see to make sure that its a compatibility issue with Windows 7. Let me post that thread at your suggested category, keep this open and monitor. I appreciate.Regards, Jignesh