OABINTEG: Checking the integrity of the offline address book (OAB)
Although it is an "old" tool, it also works quite well under Exchange 2010, although there are a few limitations (it does not check the web-based publication of the OAB). Nevertheless useful to check the creation process of the OAB and especially to compare the OAB against the Active Directory. OABINTEG can be downloaded here ... Read more