I'm using Nuxeo 5.8 and when I try to use the Preview file is returning the errors below. follows server.log:

2013-12-19 10:11:49,151 ERROR [http-bio-0.0.0.0-8080-exec-55] [org.nuxeo.ecm.platform.preview.restlet.PreviewRestlet] Could not build preview for missing blob at default org.nuxeo.ecm.platform.preview.api.PreviewException: Error during conversion

at org.nuxeo.ecm.platform.preview.adapter.base.ConverterBasedHtmlPreviewAdapter.getPreviewBlobs(ConverterBasedHtmlPreviewAdapter.java:154)
at org.nuxeo.ecm.platform.preview.adapter.base.ConverterBasedHtmlPreviewAdapter.getPreviewBlobs(ConverterBasedHtmlPreviewAdapter.java:113)
at org.nuxeo.ecm.platform.preview.adapter.base.AbstractHtmlPreviewAdapter.getFilePreviewBlobs(AbstractHtmlPreviewAdapter.java:127)
at org.nuxeo.ecm.platform.preview.restlet.PreviewRestlet.initCachedBlob(PreviewRestlet.java:204)
at org.nuxeo.ecm.platform.preview.restlet.PreviewRestlet.handle(PreviewRestlet.java:136)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.jboss.seam.util.Reflections.invoke(Reflections.java:22)
at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:31)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56)
at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:28)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:68)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.nuxeo.ecm.platform.ui.web.util.NuxeoExceptionInterceptor.aroundInvoke(NuxeoExceptionInterceptor.java:79)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:44)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107)
at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:166)
at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:102)
at org.nuxeo.ecm.platform.preview.restlet.PreviewRestlet_$$_javassist_82.handle(PreviewRestlet_$$_javassist_82.java)
at org.nuxeo.ecm.platform.ui.web.restAPI.SeamRestletFilter.doHandle(SeamRestletFilter.java:128)
at org.restlet.Filter.handle(Filter.java:134)
at org.restlet.Filter.doHandle(Filter.java:105)
at org.restlet.Filter.handle(Filter.java:134)
at org.restlet.Router.handle(Router.java:444)
at com.noelios.restlet.ext.servlet.ServletConverter.service(ServletConverter.java:129)
at org.nuxeo.ecm.platform.ui.web.restAPI.RestletServlet.service(RestletServlet.java:126)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.wss.servlet.BaseWSSFilter.doFilter(BaseWSSFilter.java:137)
at org.nuxeo.wss.servlet.FailSafeWSSFilter.doFilter(FailSafeWSSFilter.java:55)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.core.management.jtajca.internal.Log4jWebFilter.doFilter(Log4jWebFilter.java:64)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.ui.web.rest.FancyURLFilter.doFilter(FancyURLFilter.java:129)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.wi.filter.WIRequestFilter.doFilter(WIRequestFilter.java:114)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.web.common.requestcontroller.filter.NuxeoRequestControllerFilter.doFilter(NuxeoRequestControllerFilter.java:145)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.ui.web.auth.NuxeoAuthenticationFilter.doFilterInternal(NuxeoAuthenticationFilter.java:614)
at org.nuxeo.ecm.platform.ui.web.auth.service.NuxeoAuthFilterChain.doFilter(NuxeoAuthFilterChain.java:35)
at org.nuxeo.ecm.platform.ui.web.auth.oauth.NuxeoOAuthFilter.doFilter(NuxeoOAuthFilter.java:119)
at org.nuxeo.ecm.platform.ui.web.auth.service.NuxeoAuthFilterChain.doFilter(NuxeoAuthFilterChain.java:33)
at org.nuxeo.ecm.platform.ui.web.auth.NuxeoAuthenticationFilter.doFilter(NuxeoAuthenticationFilter.java:410)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.web.common.requestcontroller.filter.NuxeoCorsFilter.doFilter(NuxeoCorsFilter.java:51)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.web.common.exceptionhandling.NuxeoExceptionFilter.doFilter(NuxeoExceptionFilter.java:79)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.nuxeo.ecm.platform.web.common.encoding.NuxeoEncodingFilter.doFilter(NuxeoEncodingFilter.java:69)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Caused by: org.nuxeo.ecm.core.convert.api.ConversionException: An error occurred trying to convert file /Relação de processos na DIARQ_incompleta_alterada.xlsx to from application/vnd.openxmlformats-officedocument.spreadsheetml.sheet to text/html

at org.nuxeo.ecm.platform.convert.plugins.JODBasedConverter.convert(JODBasedConverter.java:325)
at org.nuxeo.ecm.core.convert.service.ConversionServiceImpl.convert(ConversionServiceImpl.java:168)
at org.nuxeo.ecm.platform.preview.adapter.base.ConverterBasedHtmlPreviewAdapter.getPreviewBlobs(ConverterBasedHtmlPreviewAdapter.java:147)
... 78 more

Caused by: org.artofsolving.jodconverter.office.OfficeException: task did not complete within timeout

at org.artofsolving.jodconverter.office.PooledOfficeManager.execute(PooledOfficeManager.java:100)
at org.artofsolving.jodconverter.office.ProcessPoolOfficeManager.execute(ProcessPoolOfficeManager.java:92)
at org.artofsolving.jodconverter.OfficeDocumentConverter.convert(OfficeDocumentConverter.java:86)
at org.artofsolving.jodconverter.OfficeDocumentConverter.convert(OfficeDocumentConverter.java:74)
at org.nuxeo.ecm.platform.convert.plugins.JODBasedConverter.convert(JODBasedConverter.java:283)
... 80 more

Caused by: java.util.concurrent.TimeoutException

at java.util.concurrent.FutureTask.get(Unknown Source)
at org.artofsolving.jodconverter.office.PooledOfficeManager.execute(PooledOfficeManager.java:96)
... 84 more

2013-12-19 10:11:49,224 WARN [MessageDispatcher] [org.artofsolving.jodconverter.office.PooledOfficeManager] connection lost unexpectedly; attempting restart