Calendar items missing 2

[SAMSNEED]

Lately we have noticed several items missing from outlook calendar. This problem occurs on 4 users.

Outlook configuration
----------------------
>> Calendar AutoArchive-clean out items older than 6monthes
-----------------------------------------------------------

What could be the cause of this? Could it be that the exchange corrupt is?

Network info:
---------------------------------
Windows 2000 server sp3
Exchange 2000 sp3
Windows 2000 prof. (client PC)
Norton-AntiVirus Enterprise Edition
----------------------------------

Event viewer error
---------------------------
Event Type: error + Warning
Event Source: EXCDO
Event ID: 8219 + 8230 + 8199
----------------------------

I searched for the error and i found the next article - 310440. I tried to solve the problem but with no result.

Any help would be appreciated!
Thank you