Windows Error reporting stopped one service?

Solution 1:

what made the service terminate unexpectedly

That would be hard to answer without any details - except that is has crashed. Does your application write any logfiles? Are there hints in other eventlogs?

in any case WER cause the service to terminate?

WER starts when a service has been terminated, it is not able to terminate your processes.

Windows Error Reporting is a event-based feedback infrastructure designed to gather information about the problems that Windows can detect, report the information to Microsoft, and provide users with available solutions.

Beginning with Windows Vista, Windows provides crash, no response, and kernel fault error reporting by default without requiring changes to your application. Applications instead use the WER API to generate error reports for application-specific issues that are not related to crashes, non-responses, or kernel faults.

To generate error reports for application-specific issues, the application must create a short description of the problem using a few basic pieces of information called report parameters. Report parameters include information such as the application name, application version, module name, module version, and error code. The combination of these report parameters describes a unique problem.