Calendar items do not sync fro my Treo755 to my entourage desktop

[SueF]

Version: 2004
Operating System: Mac OS X 10.4 (Tiger)
Processor: Power PC
Email Client: imap

I have checked my settings and do not understand why some of my calendar entries do not sync from my Treo755 to my Entourage desktop.
I do not have any other "identities" open, so I don't know what the log refers to which is attached below:

Additionally, my log says the following:

HotSync 3.2.1 started 10/6/08 12:22:16 PM
Local Synchronization
OK Install
OK Vindigo
OK Media
HotSync Failure: The Entourage identity "Main Identity" could not be opened because another identity is open in another Office application.
synchronization failed
Entourage Conduit synchronization failed
"Entourage Conduit" failed (error = #-1)
OK Install
Backed up EAContentDB.pdb
Backed up CarrierProfiles2.pdb
Backed up VindigoComments.pdb
Backed up Queries.pdb
Backed up FrameworkDB.pdb
Backed up CSRecordOutSyncInboxDB.pdb
Backed up CSRecordOutSyncFiledDB.pdb
Backed up CSRecordOutEAContentDB.pdb
Backed up MMIDCache3.pdb
Backed up midataidcache.pdb
Backed up Messages Database.pdb
Backed up NetworkProfiles2.pdb
Backed up Blazer URL Autofill.pdb
Backed up Blazer Field Autofill.pdb
Backed up ConduitMonitor.prc
Backed up Vindigo.prc
Backed up VSync.prc
Backed up PhoneCallDB.pdb
Backed up Cookie Data.pdb
Backed up psysLaunchDB.pdb
Backed up Saved Preferences.prc
OK Backup
Last sync time and PC ID updated on handheld
HotSync Complete 10/6/08 12:23:52 PM
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