Using Zimbra Desktop 2.01, upgraded from 1.03 (which has worked for years, with only little glitches) to 7.14, but restore and sync did not work. Un-installed, and installed v2.01: Restore from v1.03 stopped at about 3 GB, but synchronization of messages and calendar completed.
However, address book sync fails with the following message:

"Debug message: Yahoo address book synchronization failed


com.zimbra.cs.offline.ab.yab.YabImport$1: Yahoo address book synchronization failed
at com.zimbra.cs.offline.ab.yab.YabImport.serviceExce ption(
at com.zimbra.cs.offline.ab.yab.YabImport.failed(YabI
at com.zimbra.cs.offline.ab.yab.YabImport.importData(
at com.zimbra.cs.offline.OfflineImport.importData(Off
at com.zimbra.cs.offline.YMailImport.importData(YMail
at com.zimbra.cs.datasource.DataSourceManager.importD ata(
at com.zimbra.cs.datasource.DataSourceManager.importD ata(
at com.zimbra.cs.mailbox.DataSourceMailbox.syncAllLoc alDataSources(
at com.zimbra.cs.mailbox.DataSourceMailbox.sync(DataS
at com.zimbra.cs.mailbox.DataSourceMailbox.syncOnTime r(
at com.zimbra.cs.mailbox.SyncMailbox$
at java.util.TimerThread.mainLoop(Unknown Source)
at Source)

If issue persists please post description and debug information here."

Is there any idea what can be done about this?
Do I have to go back to v1.03?