I'm able to connect mobile device to the BES only if I remove from MS Exchange 2007 delivery options (grant permission and forwarding field) for the user that I want to conect to BES. As long as Delivery options are included in user mailbox account on MS Exchange 2007 Server I'm not able to connect it. On mobile device appears "An error occurred. Please contact your System Administrator".
If I connect user to the BES without switched on delivery options in MS Exchange 2007, and after sucessful activation if I switch it on, then status for that user on BES server is "No PIN"
That user is not able anymore to receive emails on mobile device.