Offline Address Book not getting downloaded locally - no error (Exchange 2010)

Description of the Issue: in Outlook - Send/Receive/Download Address Book… runs successfully, but Offline Address Book does not get downloaded.

Additional information: both mailbox server on which OAB gets generated, and CAS server to where OAB gets distributed work properly (ie. OAB gets gets generated and distributed properly – great article that helps troubleshoot the process - http://www.msexchange.org/articles-tutorials/exchange-server-2010/management-administration/offline-address-book-part3.html)

Following additional tweaks on the CAS servers fix the issue:

o   Enable Directory Browsing (IIS Manager/OAB site/Directory Browsing/Enable)

o   Assign IIS_IUSRS (CAS_ServerName\IUSRS) and Authenticated Users read permissions to OAB folder (C:\exchange server\v14\clientaccess\oab)

How to add the list of email addresses to the single mailbox

If you have a txt file with the email addresses to add to the single mailbox you can run following PS script in MS Exchange Management Shell (Exchange 2010 - should work on Exchange 2007 too):
1. $a = Get-Content c:\emailaddresses.txt

(this get content of emailaddresses.txt file with email addresses in it to the variable $a, which is the array)

2. foreach ($b in $a) {set-mailbox user1@yourdomain.com -emailaddresses @{Add=$b} }

(as you see, it's a cycle, where it picks up an item out of array $a to the variable $b and for every item in the array $a, command adds it to the mailbox user1@yourdomain.com)

Autodiscover for Exchange (Outlook) and Offline Address Book; Out of Office Assistant

It is a well documented fact that _autodiscover._tcp SRV record in the userdomain.com DNS zone is needed for the proper autodiscover work in Outlook (and also Offline Address Book download in cached mode and Out of Office Assistant setup).

In addition autodiscover.userdomain.com A (or CNAME) record might be needed as well.

Usually _autodiscover._tcp.userdomain.com SRV record is enough for configuration to work properly, but it seems like autodiscover.userdomain.com is being queried first and if that query fails, it queries _autodiscover._tcp.userdomain.com: I had an instance that the userdomain.com zone did not have autodiscover A record and even though other zones with similar configuration worked fine, the particular one users had problems with autodiscover.