com.zimbra.cs.mailbox.OfflineServiceException: must upgrade to all-new yahoo calendar service
ExceptionId:mid=4:1236069365734:4db8653e10755795
Codeffline.YCALDAV_NEED_UPGRADE
at com.zimbra.cs.mailbox.OfflineServiceException.YCAL DAV_NEED_UPGRADE(OfflineServiceException.java:96)
at com.zimbra.cs.offline.OfflineCalDavDataImport.doCa lDavFailures(OfflineCalDavDataImport.java:58)
at com.zimbra.cs.offline.OfflineCalDavDataImport.impo rtData(OfflineCalDavDataImport.java:50)
at com.zimbra.cs.offline.YMailImport.importData(YMail Import.java:98)
at com.zimbra.cs.datasource.DataSourceManager.importD ata(DataSourceManager.java:154)
at com.zimbra.cs.mailbox.LocalMailbox.importData(Loca lMailbox.java:417)
at com.zimbra.cs.mailbox.LocalMailbox.syncAllLocalDat aSources(LocalMailbox.java:389)
at com.zimbra.cs.mailbox.LocalMailbox.sync(LocalMailb ox.java:431)
at com.zimbra.cs.mailbox.LocalMailbox.syncOnTimer(Loc alMailbox.java:361)
at com.zimbra.cs.mailbox.DesktopMailbox$1.run(Desktop Mailbox.java:436)
at java.util.TimerThread.mainLoop(Unknown Source)
at java.util.TimerThread.run(Unknown Source)

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