Exchange 2010 Offline address book error

Please can you let me know how to get rid of this error..

Log Name:      Application
Source:        MSExchangeSA
Date:          05/04/2012 06:08:15
Event ID:      9390
Task Category: (13)
Level:         Warning
Keywords:      Classic
User:          N/A
Computer:      BRPRVNW02.UKDatanet.net
Description:

OALGen failed to find the OAB version 4 manifest file '\\BRPRVNW02\ExchangeOAB\35535b98-1594-4c92-b810-c5d0ce9ba497\oab.xml'. This is normal if it is the first time this offline address list has been published to the file system.  Check other logged events to see if this is a serious error.


I check the folder and yes the folder is empty. how do i create the file.. also i looked it up on the internet and all the info and recomendations are for exchange 2007. i have tryed the fix suggestions but it still appears...

Also it doesn't seem to have any nock on effect as it doesn't seem to be effecting anything.
So i could just ignore it but i do really want to keep my events log clean..

thanks

Thanks