java.lang.IllegalArgumentException: number of workunits cannot be negative
   at org.netbeans.modules.progress.spi.InternalHandle.toDeterminate(InternalHandle.java:193)
   at org.netbeans.api.progress.ProgressHandle.switchToDeterminate(ProgressHandle.java:134)
   at org.netbeans.modules.maven.indexer.RemoteIndexTransferListener.transferStarted(RemoteIndexTransferListener.java:105)
   at org.apache.maven.wagon.events.TransferEventSupport.fireTransferStarted(TransferEventSupport.java:104)
   at org.apache.maven.wagon.AbstractWagon.fireGetStarted(AbstractWagon.java:543)
   at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:306)
   at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:287)
   at org.apache.maven.wagon.StreamWagon.getIfNewer(StreamWagon.java:97)
   at org.apache.maven.wagon.StreamWagon.get(StreamWagon.java:61)
   at org.apache.maven.index.updater.WagonHelper$WagonFetcher.retrieve(WagonHelper.java:219)
   at org.apache.maven.index.updater.WagonHelper$WagonFetcher.retrieve(WagonHelper.java:201)
   at org.apache.maven.index.updater.DefaultIndexUpdater.loadIndexDirectory(DefaultIndexUpdater.java:191)
   at org.apache.maven.index.updater.DefaultIndexUpdater.access$300(DefaultIndexUpdater.java:76)
   at org.apache.maven.index.updater.DefaultIndexUpdater$LuceneIndexAdaptor.setIndexFile(DefaultIndexUpdater.java:642)
   at org.apache.maven.index.updater.DefaultIndexUpdater.fetchAndUpdateIndex(DefaultIndexUpdater.java:862)
   at org.apache.maven.index.updater.DefaultIndexUpdater.fetchAndUpdateIndex(DefaultIndexUpdater.java:157)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.indexLoadedRepo(NexusRepositoryIndexerImpl.java:505)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.access$200(NexusRepositoryIndexerImpl.java:119)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl$3.run(NexusRepositoryIndexerImpl.java:573)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl$3.run(NexusRepositoryIndexerImpl.java:566)
   at org.openide.util.Mutex.writeAccess(Mutex.java:404)
   at org.netbeans.modules.maven.indexer.NexusRepositoryIndexerImpl.indexRepo(NexusRepositoryIndexerImpl.java:566)
   at org.netbeans.modules.maven.indexer.api.RepositoryIndexer.indexRepo(RepositoryIndexer.java:58)
   at org.netbeans.modules.maven.repository.RepositoryNode$RefreshIndexAction$1.run(RepositoryNode.java:241)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1423)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)