Missing messages, Corrupt Content Cache

Hi,

One of the archive folder status is showing yellow triangle with exclaimation mark within and the status shown as missing messagesm corrupt content cache. I have tried to reindex the folder without success and the event viewer shown

"Failed to Unpack Msg: F:\EMC SourceOne Work\ExIndexTemp\archive_201101_001\4EA285708F8EE7C56B622867D5BC1219BE0A4B57A5A93AEF00.emcmf (0x86042B1B) [ExAsIdxObj.exe, IdxRebuild.cpp(944).IndexThread::ReBuildVolIndex] "

Any clue on how to fix this?

Our Environment :

1. Sourceone 6.6
   
2. SQL 2005
   
3. Windows 2003 sp 2
   
4. Exchange 2003
   

Regards,

MW