Exmerge the mailboxes in the old Exchange server

Hi ALL,
We are trying to Exmerge the mailboxes in the old Exchange server INEXC747. As all the mailboxes are migrated, Exmerge fails. Referring the Exmerge log.(Information store service is very much running, something to do with the Permissions it seems) Would like to know how did anyone handle with this?
Regards, RAJ
