Activating problem - unable to retrieve specific device attributes from the device

[fam555]

Hello, BlackBerry guys,

I have configured a BlackBerry Enterprise Server Express 5.02 for our organization. The BESX is running on Windows Server 2008 R2 ST, and works with Exchange 2010 SP1. There are 3 Exchange server: 1 HUB/CAS, and 2 Mailbox servers.

The installation has gone smoothly. And everyting works fine, activating ~ 20 BlackBerry users.

Today I am not able to associate a device to a user via BAS (BlackBerr Administration Service), getting error:
"The BlackBerry Administration Service was unable to retrieve specific device attributes from the device that is connected to your computer"

I've checked a thousand times all permissions, CAL, all deployment steps in official BlackBerry deployment guide, KB20015, try to fix

registry (KB03304), fixed throttling policy (KB20608).

"IEMSTEST" passed successfully:
-----------------------------------
user: Opening message store using
/o=Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/
cn=Recipients/cn=user
/o=Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/
cn=Configuration/cn=Servers/cn=HUBCASSERVER/cn=Microsoft Private MDB
user: Mailbox opened successfully
user: Root Folder opened successfully
user: Folder created successfully
user: Test folder deleted successfully
user: MAPI test completed successfully
user: CDO Server Name: HUBCASSERVER
user: CDO Mailbox DN: /o=General Financing/ou=Exchange Administrative Group
(FYDIBOHF23SPDLT)/cn=Recipients/cn=user
user: CDO logon successful
user: Get default calendar folder successful
user: Get calendar folder name successful: 'Calendar'
user: CDO test completed successfully
user: Active Directory permissions test completed successfully
user: Initializing EWS Proxy... successful
user: Configuring User... successful
user: EWS calendar find request... successful
-----------------------------------

Restarting BlackBerry services, configuring some BESX server settings via BAS (for example "settings set to "Activate any PIN", changed it to "NO", saved, changed back to "Activate any PIN" and saved"), sometimes fixed the problem, but it repeats again after several hours.

Also Internet Explorer always stop working when first time logging into BAS.

Any help would be greatly appreciated.
Thanks in advance!