Having performed some refactoring I am now finding that NCoverExplorer is unable to merge my test results. With NCover and NCoverExplorer v3.2.2 the merge appeared to work, but NCoverExplorer would fail to open the merged file with an error suggesting that the file didn t exist or couldn t be opened (which it did and could).

So I tried with NCover 1.5.8 and I get the following, more helpful error from NCoverExplorer 3.2.2 when it tries to merge the files:

NCoverExplorer.Console Complete v3.2.2 x86 (Administrator)
(c) 2007 - 2009 Gnoso Inc.
http://www.ncover.com/

Processing report settings from the command line.

-- Top-level exception (System.Exception)
An error occurred while loading your coverage file: Duplicate method was added.
-- Stack Trace
   at NCover.Framework.Reports.ReportingProcessor.CreateCoverageView(List`1 filenames, ICoverageReportSettings sett)
   at NCover.Framework.Reports.ReportingProcessor.Process()
   at NCoverExplorer.Console.EntryPoint.Main(String[] args)
-- Inner exceptions
Duplicate method was added.
-- Stack Trace
   at NCover.Framework.Models.NCover2.NCover2CoverageClass.CreateMethod(String name, String signature, Int32 cyclomaticComplexity, Boolean doNotAppend)
   at NCover.Framework.Models.NCover2.NCover2CoverageClass.CreateMethod(String name, String signature, Int32 cyclomaticComplexity)
   at NCover.Framework.Models.Merge.MergeCoverageModel.ProcessMethods(ICoverageModelClass destClass, ICoverageModelClass sourceClass, Dictionary`2 documentMa
p, Boolean isMerge)
   at NCover.Framework.Models.Merge.MergeCoverageModel.ProcessClasses(ICoverageModelModule destModule, ICoverageModelNamespace destNs, ICoverageModelNamespac
e sourceNs, Dictionary`2 documentMap, Boolean isMerge)
   at NCover.Framework.Models.Merge.MergeCoverageModel.ProcessNamespaces(ICoverageModelModule destModule, ICoverageModelModule sourceModule, Dictionary`2 doc
umentMap, Boolean isMerge)
   at NCover.Framework.Models.Merge.MergeCoverageModel.ProcessModules(ICoverageModel model, Dictionary`2 documentMap, Boolean isMerge)
   at NCover.Framework.Models.Merge.MergeCoverageModel..ctor(ICoverageModel model, MergeFilterMode mode)
   at NCover.Framework.Utilities.CoverageLoader.Merge(ICoverageView originalView, List`1 paths, MergeFilterMode mode)
   at NCover.Framework.Utilities.CoverageLoader.Merge(List`1 paths, MergeFilterMode mode)
   at NCover.Framework.Reports.ReportingProcessor.CreateCoverageView(List`1 filenames, ICoverageReportSettings sett)


Exiting with return code: 2

How do I go about resolving this error? The clues are there - seeing the name and signature parameters to CreateMethod() would probably help a lot.