Sheet contains errors - Destination exists and is not a directory error

Sheet contains errors.

Destination exists and is not a directory: /opt/datameer/Datameer-5.4.2/cache/dfscache/wb-preview-1234/MySheet/data

[datameer_user] WARN [2015-01-01 00:00:00.000] qtp1030870354-186578 - Handler execution resulted in exception

java.lang.RuntimeException: Could not generate preview for sheet 'Sheet4'. FileNotFoundException: Destination exists and is not a directory: /opt/datameer/Datameer-5.4.2/cache/dfscache/wb-preview-1234/MySheet/data

at datameer.dap.conductor.service.preview.WorkbookPreviewService1.createSheetPreview(WorkbookPreviewService1.java:172)

at datameer.dap.conductor.service.preview.WorkbookPreviewService1.createSheetPreview(WorkbookPreviewService1.java:115)

at datameer.dap.conductor.service.preview.WorkbookPreviewService1.createSheetPreview(WorkbookPreviewService1.java:109)

at datameer.dap.conductor.service.visualization.ColumnMetricsService.getActualSource(ColumnMetricsService.java:120)

at datameer.dap.conductor.service.visualization.VisualizationService.getFlipsideVisualization(VisualizationService.java:80)

at datameer.dap.conductor.webapp.controller.workbook.VisualizationController.getSheetVisualization(VisualizationController.java:70)

at sun.reflect.GeneratedMethodAccessor455.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:497)

at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)

at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:436)

at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:424)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:669)

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:574)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)

at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:769)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1667)

at datameer.dap.conductor.webapp.filter.MinifyJsCssFilter.doFilter(MinifyJsCssFilter.java:49)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.HeaderInjectFilter.doFilter(HeaderInjectFilter.java:24)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.CsrfFilter.doHttpFilter(CsrfFilter.java:85)

at datameer.dap.conductor.webapp.filter.CsrfFilter.doFilter(CsrfFilter.java:64)

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.SessionFilter.doFilter(SessionFilter.java:53)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.RestAuthenticationOriginFilter.doFilter(RestAuthenticationOriginFilter.java:52)

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at org.eclipse.jetty.servlets.UserAgentFilter.doFilter(UserAgentFilter.java:83)

at org.eclipse.jetty.servlets.GzipFilter.doFilter(GzipFilter.java:364)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.OptimisticLockRetryFilter.doFilter(OptimisticLockRetryFilter.java:31)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.PermissionDeniedExceptionFilter.doFilter(PermissionDeniedExceptionFilter.java:29)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.RequestMetaDataFilter.doFilter(RequestMetaDataFilter.java:27)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at datameer.dap.conductor.webapp.filter.PersistenceFilter.doFilter(Unknown Source)

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650)

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)

at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)

at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)