Adobe Experience Manager as a Cloud Service (AEMaaCS)中的复制队列有时可能会被阻止。 按照本文中的步骤操作，使用管理员权限修复此问题。
描述
环境
Adobe Experience Manager as a Cloud Service
问题/症状
由于javax.jcr.NamespaceException: Unknown namespace prefix: ns22_exception，AEMaaCS复制队列之一定期被阻止。
栈栈跟踪：
[ EventAdminAsyncThread #3] org.apache.sling.distribution.journal.impl.publisher.DistributionPublisher [ null] Message: Failed attempt (37/infinite) to import the distribution package PackageMessage(pubSlingId=d5e89d11-a40d-4b3f-a8f4-ee478c5b91aa, reqType=ADD, pkgId=dstrpck-1698635668289-1c825ebd-f03d-4d56-97b4-790c169facdc, pkgType=journal_filevault, pkgLength=41118, pubAgentName=publish, userId=replication-service, paths=[ /content/dam/product/photography/129/12999/1299989/PS1299989-731_HB.tif] , deepPaths=[ ] ) at offset=74663574 because of 'javax.jcr.RepositoryException: Some errors occurred while installing packages. Please check the logs for details. First exception is logged as cause.', the importer will retry later,
Stacktrace: org.apache.sling.distribution.common.DistributionException: javax.jcr.RepositoryException: Some errors occurred while installing packages. Please check the logs for details. First exception is logged as cause.
at org.apache.sling.distribution.serialization.impl.vlt.FileVaultContentSerializer.importFromStream(FileVaultContentSerializer.java:159)
at org.apache.sling.distribution.packaging.impl.InMemoryDistributionPackageBuilder.installPackageInternal(InMemoryDistributionPackageBuilder.java:119)
at org.apache.sling.distribution.packaging.impl.AbstractDistributionPackageBuilder.installPackage(AbstractDistributionPackageBuilder.java:156)
at org.apache.sling.distribution.monitor.impl.MonitoringDistributionPackageBuilder.installPackage(MonitoringDistributionPackageBuilder.java:92)
at org.apache.sling.distribution.serialization.impl.vlt.VaultDistributionPackageBuilderFactory.installPackage(VaultDistributionPackageBuilderFactory.java:317)
at org.apache.sling.distribution.journal.bookkeeper.PackageHandler.installAddPackage(PackageHandler.java:78)
at org.apache.sling.distribution.journal.bookkeeper.PackageHandler.apply(PackageHandler.java:61)
at org.apache.sling.distribution.journal.bookkeeper.BookKeeper.importPackage(BookKeeper.java:155)
at org.apache.sling.distribution.journal.impl.subscriber.DistributionSubscriber.processQueueItem(DistributionSubscriber.java:396)
at org.apache.sling.distribution.journal.impl.subscriber.DistributionSubscriber.fetchAndProcessQueueItem(DistributionSubscriber.java:348)
at org.apache.sling.distribution.journal.impl.subscriber.DistributionSubscriber.processQueue(DistributionSubscriber.java:326)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: javax.jcr.RepositoryException: Some errors occurred while installing packages. Please check the logs for details. First exception is logged as cause.
at org.apache.jackrabbit.vault.fs.io.Importer.run(Importer.java:579)
at org.apache.sling.distribution.serialization.impl.vlt.FileVaultContentSerializer.importFromStream(FileVaultContentSerializer.java:151)
... 11 more
Caused by: org.apache.jackrabbit.vault.packaging.PackageException: Error creating/updating node /content/dam/product/photography/129/12999/1299989/PS1299989-731_HB.tif/jcr:content/metadata
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1177)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:976)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.commit(Importer.java:1018)
at org.apache.jackrabbit.vault.fs.io.Importer.run(Importer.java:531)
... 12 more
Caused by: javax.jcr.NamespaceException: internal error: failed to resolve namespace prefix
at org.apache.jackrabbit.spi.commons.namespace.SessionNamespaceResolver.getURI(SessionNamespaceResolver.java:62)
at org.apache.jackrabbit.spi.commons.conversion.NameParser.parse(NameParser.java:189)
at org.apache.jackrabbit.spi.commons.conversion.ParsingNameResolver.getQName(ParsingNameResolver.java:64)
at org.apache.jackrabbit.spi.commons.conversion.DefaultNamePathResolver.getQName(DefaultNamePathResolver.java:74)
at org.apache.jackrabbit.vault.fs.impl.io.DocViewImporter.updateExistingNode(DocViewImporter.java:1054)
at org.apache.jackrabbit.vault.fs.impl.io.DocViewImporter.addNode(DocViewImporter.java:947)
at org.apache.jackrabbit.vault.fs.impl.io.DocViewImporter.startDocViewNode(DocViewImporter.java:406)
at org.apache.jackrabbit.vault.fs.impl.io.DocViewSAXHandler.startElement(DocViewSAXHandler.java:348)
at java.xml/com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(AbstractSAXParser.java:510)
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(XMLNSDocumentScannerImpl.java:374)
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2710)
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:605)
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:112)
at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:534)
at java.xml/com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:888)
at java.xml/com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:824)
at java.xml/com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at java.xml/com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1216)
at java.xml/com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:635)
at java.xml/com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl.parse(SAXParserImpl.java:324)
at org.apache.jackrabbit.vault.fs.io.DocViewParser.parse(DocViewParser.java:254)
at org.apache.jackrabbit.vault.fs.impl.io.AbstractArtifactHandler.importDocView(AbstractArtifactHandler.j