We are using RFA7 libraries for getting the data from Reuters.
At rare intervals, we are facing "AccessViolationException" thrown by the libraries due to which the WCF service hosted on windows service is getting crashed.
As you running WCF app so that I assume that you are using RFA.NET 7.x, is this correct? Please note that RFA.NET 7.x is now end of support and we strongly suggest you upgrade it to RFA.NET 8.1.x which is the latest version which contains the fix for many issues in RFA C++ and RFA.NET layer. It can avoid an issue which already fixed between the old and the new version.
Also, I would suggest you investigate the crash in your application at the first steps. At least you should be able to get the stack trace from the crash.
-Can you save the crash to minidump? and does it point to any codes in RFA7 lib? and Is there any log generate under folder %TEMP% of your windows? as far as I understand if it's the crash from RFA lib, RFA has its own internal thread which can catch the exception and write it to the %TEMP% folder. However, the application may need to deploy the RFA PDB files in the running directory as well.
If the call stack point to the codes in RFA, please contact RDC named user in your company to open a new support ticket to API support directly.